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How to Recover Deleted Pictures or Files – Data Recovery Tools and Techniques

Trashed hard driveHelp, I lost My Pictures!

If you lost or accidentally deleted your pictures and files, there are still great chances to recover them. As a computer geek, (I do this as a profession), I had to recover file many times. In the vast majority of time the files are recoverable, and in about 30 percent of the cases the retrieval is instant.

The key to a successful retrieval of your pictures and files is to act as soon as you discovered you lost the files, be it because an accidental deletion, or computer problems. I will explain this later in the document.

This tutorial is created for Windows computers, and it assumes you have a minimum knowledge of operating in a Windows Operating System. If you don’t know how to operate in a Windows environment, your best bet is to go to a local computer repair shop.

How To Recover Deleted Pictures or Files?

The Computer IS Fine, But My Files Are Gone

If the computer is fine and it doesn’t behave erratically, most likely you accidentally deleted your files. The first step in this case is to check in the Recycle Bin, but I bet you already did this. If you didn’t do it now. Look for pictures or maybe just a folder, If you accidentally deleted the whole folder, you won’t see the files or the pictures in the Recycle Bin, you will have to look for the folder that contains the files. This is particularly difficult if your Recycle Bin hasn’t been emptied in a while, and you have to search through thousands of files.

How to Recover Deleted Files from Recycle Bin – Advanced Tutorial

Sorting the Items In the Recycling Bin

If your Recycle Bin is empty, or you have few items, you can skip this.
To make it easier right click in the “Recycle Bin” folder and choose sort by “Date deleted”.
If the deletion was made long time ago this doesn’t make sense, and you would probably need to sort by type. Sort by type is not available by default on the Recycle bin, so you have to activate it. Right click in the Recycle Bin folder, select “Sort By”, and the choose “More”. Scroll down on the list and check the box for “Type”. Now the “Sort by type” is available from the contextual menu. When you sort by type all the folders are displayed grouped so it’s easier to find your pictures folder if it’s in the recycle bin.

httpv://www.youtube.com/watch?v=10ERJcqMWIg

Recover Deleted Pictures or Files Using “Previous Versions”
Recovering with Windows 7 Previous Versions
If your operating system is not Windows 7, you can skip this paragraph, this feature is only available on Windows 7.
If your files are located on the System drive, usually the C: drive, “Previous Version” is enabled by default. “Previous Version” it’s a feature that allows the system to store on a hidden portion of the drive, files and system settings. The files are automatically copied on the hidden folder, and stored for a limited numbers of days. When a file is modified, or deleted, the old version is stored automatically. Let’s say you deleted some pictures in the “Pictures” folder. Go to “My Computer” => C: => Users => USERNAME . Search for the “My Pictures” folder and right click on the folder. From the contextual menu select “Restore Previous Versions”. A list with snapshots of the folder will be presented. Select a previous version that you think contains the deleted files. If you accidentally deleted the files today at 11:00 AM, any snapshot previous to this date and time would contain the deleted files. Neat huh? The trick here is to act as soon as you deleted the files. The longer you wait the bigger the chances to get the good snapshot deleted are. The snapshots are deleted on a regular basis by the system, so if you wait too long, the files will be deleted.

httpv://www.youtube.com/watch?v=jnPI9p9rNkY

Lexar Media IR437 Image Rescue Software (Retail Package)

Recover your lost or deleted files with this easy to use software. The software will scan raw data on you memory card, and it will find your lost pictures.
Lexar Image Rescue has an intuitive and easy to use interface, and will scan the mass storage device, (sd cards, USB drives), for deleted image files or after reformatting your SD card. Additionally, the newest version of the software, can recover, not only image files, but many other popular document types.

This is probably one of the easiest, and most effective image recovery software.

Data Recovery Tools

Recovering Deleted Files with Data Recovery Tools

If the two methods described above didn’t work for you, that means the data has been erased from the disk. The good news is that operating systems do not really delete the files when you delete them, the OS only deletes the record from the index, so from the OS’s perspective the file doesn’t exist anymore. This is where the data recovery software comes in handy. The data recovery software scans the drive for possible files that are deleted from the index, and reassembles them for you.

As with any other recovery method the key is to act as soon as possible. The more you use your drive after the deletion, the less chances you have for a full recovery. This happens because Windows treats the portion occupied by your lost files as empty, and will start to write new data over your deleted files. The more you use the drive the more deleted data is overwritten.

The data recovery software is usually an intuitive program that can be installed on the computer, or can generate a bootable media. The purpose of the bootable media is to avoid the use of the hard drive, to maximize the chances of a full recovery, or sometimes provide an environment for un-bootable systems.
The process of recovering data with tools is very easy, and it is somewhat similar for all software, but not all data recovery programs are the same. The scanning algorithm, the reading approach are things that can make or break a recovery utility.

A few general rules for all recovery software:
To avoid further data corruption, mount the corrupted drive on another intact system. You can do this in a couple of ways:
Install the software on a separate system and attach the drive with a USB enclosure or adapter.
Create the recovery media on another computer and boot the computer with the bad drive from the bootable recovery media
Only start doing the job when you have enough time to dedicate. If you start and stop, and then start again you risk to lose more data.

How Can I Recover My Pictures After Formatting the SD Card

Pictures Recovery after Deletion or Formatting with Recovery Software

If you accidentally deleted your photos on the SD card there is no Recycle Bin for the SD card, so there is no easy way to recover them. Also it happens quite often to format your SD card and to realize that you didn’t save the pictures yet. What do we do in cases like this?
Fortunately, there is software that makes the recovery for cases like this a breeze. One of the easiest to use programs is “Sandisk RescuePro Recovery Software”.

Sandisk RescuePro Recovery Software, V3.3 Disk

It works on and card not just on Sandisk cards. It is really easy to use, and in most of the cases it is able to recover your pictures. One thing about this is that you need to wait the code for the software for a few days, but is worth. The software is actually an annual subscription, but it is very affordable.

Remember, if you deleted the pics on your card, or formatted the card, you need to stop using it immediately to insure a good recovery rate.

Recover Files from A Defective Computer

How To Recover Pictures and Files from A Defective Computer

Your computer might be defective and it won’t start. What to do in this case? First you need to assess the state of the computer and why the computer won’t start. Depending on this, you might be able to recover your files or not. In the next paragraphs I will give you tips to know what is wrong with your computer, and what to for each case.

  • If your computer boots and you can get on your Windows account, then probably the files were accidentally deleted.
  • If your computer passes the initial boot sequence but stops when loading Windows, it is the operating system that is corrupted. A re-installation could fix it, or a boot rescue CD could also fix the OS. Sometimes this could be due to bad computer RAM memory.
  • If your computer doesn’t pass the initial black screen booting sequence, something more serious could have happened, such as a defective hdd, or some other hardware problem.
  • If the computer doesn’t do anything, it is also a hardware problem. You can tackle this with a local computer shop, or proceed to moving your drive on another computer.
  • If the computer starts but it doesn’t recognizes your hard-drive, then you cannot rescue your files anymore. Actually there are data recovery services, that will disassemble your drive, and will read the data on the platters with special equipment. These are special services and are very expensive. Most of us prefer to lose the family pictures than to pay for these services.

What To Do If The Computer Won’t Boot

My Computer Won’t Boot, I Need My Pictures And Files

There are many reasons why your computer won’t boot. If you think your computer is not worth investing too much work to revive it, then the easiest way to recover your files is to take out the old hard-drive, mount it on a USB enclosure, and read it through USB on a good computer. You will be able to read your old files without any problems. This method assumes your hard-drive is not defective.For the case that Windows won’t boot because of a file-system corruption, or other Windows corruption problems, there is the Recovery Boot Disk that will allow you to boot your computer and fix a wide range of problems.

If the hard disk is the one that caused your computer to not boot, you still have good chances to recover your files, but in many cases you need a data recovery software like Data Rescue PC 3, to scan for files on the corrupted disk.

If the computer warns you before booting that there is a problem with the disk drive, you need to stop immediately using the drive if you want to maximize your chances of recovering the data. If your drive is making clicking noises, you also need to stop using it. Sometimes a hard-disk will have just enough life for a last run, so after recovery it will die.
The next step is to acquire data recovery software and install it on a good computer, and buy a USB enclosure and use it to mount the drive from the defective computer. Now connect the hard-drive to recover on the good computer and start the recovery.

Data Loss Prevention

What can I do to prevent data corruption or data loss?

  • Enable in BIOS and on the hard-drive S.M.A.R.T. This is a software utility embedded on the hard-drive that will detect when too many error corrections are occurring. Whenever this happens it means that you drive is near an imminent failure and you should backup/replace it.
  • If a message of a hard drive error appears, stop using your computer until you change the drive. You can use the computer to make a backup of your data onto another drive.
  • Check old backup tapes and copy them onto new tapes, using a temporary restore. This should happen each 10 years or more.
  • Check the data stored on CD’s and DVD’s, and recopy that media regularly. Not all CD and DVD media are equal. The factory-recorded media is the longest lasting. The media burned at home or on a computer CD-ROM unit can last between 1 to 10 years or more. So it is wise to rerecord it after a few years if you bought good quality media, or after one year if it’s on cheap media.
  • Buy an antivirus and keep it up to date.

How to Install Squid with Active Directory Authentication on Debian

How to Install Squid with Active Directory Authentication on Debian

Squid is a caching proxy software, licensed under GNU GPL, (free software).
It can help your Organization to reduce bandwidth and improves response times by caching and reusing frequently-requested web pages.
Squid has extensive access controls and if you don’t mind Command Line Interface is not too hard to configure. It runs on most available operating systems including Windows.
The following article is a step by step HOW TO Install Squid on Debian. Most of the steps are easily applicable to any other Linux distribution such as: RedHat, Suse, Ubuntu, etc…

Hardware requirements

Choose the machine wisely – if you are running a 50 computers Network a PIII should be enough provided that all you do is Web Caching and Filtering.
The memory is the most important and after that the disk speed. If you plan your proxy for a bigger Network you should consider using SCSI drives or SAS, and a faster CPU.
Memory requirements are explained later in the document.

Package Installation

Instal Debian minimal. The install cd, (only 650Mb) should be enough for this.
Reboot after installing and add packages with Aptitude (grafical interface) or "apt-get install program".
Add the following packages:
Openldap
Samba
Kerberos apt-get install krb5-{admin-server,kdc}
PAM apt-get install libpam0g-dev
Squid
Apache if you want proxy Auto-Configuration apt-get install apache2
Dansguardian if you need advanced WEB filtering
SARG if you want a log analyzer for your WEB access/filter

– – – – – – – – – – – – – – – – – – – – – –

Configure Samba

Samba is going to be used for authentication.
Note that if you run squid in transparent mode the authentication will not work.

#nano -w /etc/samba/smb.conf

Add or remove daemons to autostart
#update-rc.d  winbind defaults
#update-rc.d  samba defaults

– – – – – – – – – – – – – – – – – – – – – –
[global]
netbios name = proxy
realm = SUBDOMAIN.DOMAIN.ROOT
workgroup = SUBDOMAIN
security = ADS
password server = server1.subdomain.domain.root server2.subdomain.domain.root
socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
idmap uid = 10000-20000
domain master = no
local master = no
preferred master = no
winbind enum groups = yes
winbind enum users = yes
winbind uid = 10000-20000
winbind gid = 10000-20000
winbind separator = +
winbind use default domain = Yes
encrypt passwords = yes
log level = 5 passdb:5 auth:10 winbind:5
server string = proxy
dns proxy = no
log file = /var/log/samba/log.%m
max log size = 1000
syslog only = no
syslog = 0
encrypt passwords = true
load printers = no

– – – – – – – – – – – – – – – – – – – – – –
Do not add other parameters to the configuration file as they are not needed.
You can always tweak your configuration file later on if you need additional tweaking. If you do need further modifications do one at a time and test it extensively before release to production.
After editing smb.conf run the following command
# testparm
This will test your samba configuration file against any errors.
If there are no errors restart samba:
proxy:~# /etc/init.d/samba restart
proxy:~# /etc/init.d/winbind start
– – – – – – – – – – – – – – – – – – – – – –
Add the server to the domain
#net ads join "Ottawa Computers/Servers" -U Administrator -S server1.sub-domain.domain.edu
If you have Windows 7 you might get this in your /var/log/samba/log.wb: "NTLM CRAP authentication for user returned NT_STATUS_INVALID_PARAM"
If you get it follow the instructions below to tell Windows to use NTLM version1. Note that this is a security downgrade and it opens the door for an SMB man-in-the-middle attack. Asses the risks and the advantages before you do the change.

Run local GP on W7 gpedit.msc and look for:
Local Policies Security Options Network security: LAN Manager authentication level
Change from "Not Defined" to "LM & NTLM – Use NTLMv2 session if negotiated"
– – – – – – – – – – – – – – – – – – – – – –

Configure Squid

Make a backup copy of the default configuration file:
# cp /etc/squid/squid.conf /etc/squid/squid.conf.original
Edit the file squid.conf:
#nano –w /etc/squid/squid.conf
Replace everything in the file with the below text:

– – – – – – – – – – – – – – – – – – – – – –

#Proxy configurationuration - /etc/squid.squid.conf

# AUTHENTICATION
# -----------------------------------------------------------------------------
auth_param ntlm program /usr/bin/ntlm_auth --helper-protocol=squid-2.5-ntlmssp
auth_param ntlm children 30
auth_param basic program /usr/bin/ntlm_auth --helper-protocol=squid-2.5-basic
auth_param basic children 5
auth_param basic realm Squid Proxy Server
auth_param basic credentialsttl 2 hours
acl authenticated_users proxy_auth REQUIRED
http_access allow authenticated_users
auth_param ntlm keep_alive on

# ACCESS CONTROLS
# -----------------------------------------------------------------------------
#Deafult acl’s
acl all src all
acl manager proto cache_object
acl localhost src 127.0.0.1/32
acl to_localhost dst 127.0.0.0/8

#Declare your local network and any additional subnets
acl localnet src 192.168.100.0/24                # RFC1918 possible internal network
#acl remotesite src 192.168.200.0/24

#You would like that some of the users to be excluded from the logging.
###acl bosses src 192.168.100.255/30
###log_access deny bosses

#Tell Squid to not log google.ca
#Define the acl for google using regex
acl google url_regex ^http://www.google.ca
#Deny logging the acl
log_access deny google

#Allow the access for your localnet.
http_access allow localnet
#http_access allow remotesite

#Define allowed ports
acl SSL_ports port 443                    # https
acl SSL_ports port 563                    # snews
acl SSL_ports port 873                    # rsync
acl Safe_ports port 80                    # http
acl Safe_ports port 21                    # ftp
acl Safe_ports port 443                  # https
acl Safe_ports port 70                    # gopher
acl Safe_ports port 210                  # wais
acl Safe_ports port 1025-65535  # unregistered ports
acl Safe_ports port 280                  # http-mgmt
acl Safe_ports port 488                  # gss-http
acl Safe_ports port 591                  # filemaker
acl Safe_ports port 777                  # multiling http
acl Safe_ports port 631                  # cups
acl Safe_ports port 873                  # rsync
acl Safe_ports port 901                  # SWAT
acl purge method PURGE
acl CONNECT method CONNECT

http_access allow manager localhost
http_access deny manager
http_access allow purge localhost
http_access deny purge
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
http_access allow localnet
http_access allow localhost

# And finally deny all other access to this proxy
http_access deny all

# NETWORK OPTIONS
# -----------------------------------------------------------------------------
http_port 3128

# MEMORY CACHE OPTIONS
# -----------------------------------------------------------------------------
#The memory needed for caching used files. The more you have the faster works. (No disk access.)
cache_mem 256 MB
#Objects bigger than this should be stored on the hard-drive. This can be lower than 8kb if your server has little memory.
maximum_object_size_in_memory 8 KB

# DISK CACHE OPTIONS
# -----------------------------------------------------------------------------
#Make sure you have enough space. And mount this on a fast disk or a raid0.
##cache_dir ufs /var/squid/cache 1000 16 256
cache_dir diskd /var/squid/cache 500 16 256

#This is extremely useful if your users download big files. You can even increase this depending on usage.
maximum_object_size 40960 KB

# LOGFILE OPTIONS
# -----------------------------------------------------------------------------
#This logging format includes the date the address requested the IP address of the requestor and the AD user who made the request.
#Human resources need to know what your users browse during the workday.
logformat squid %tl %6tr %>a %Ss/%03Hs %<st %rm %ru %un %Sh/%<A %mt
#Where to store all of this data.
access_log /var/log/squid/access.log squid

# ADMINISTRATIVE PARAMETERS
# -----------------------------------------------------------------------------
cache_mgr admin@mycompany.net
mail_from squid@ mycompany.net
visible_hostname proxy

# DNS OPTIONS
# -----------------------------------------------------------------------------
##You have the option to use the ISP’s DNS here
# dns_nameservers 10.0.0.1 192.168.0.254
hosts_file /etc/hosts
uri_whitespace allow
http_access deny all

#### --- End of the configuration file --- ####

– – – – – – – – – – – – – – – – – – – – – –

Run the command squid –z to let squid create the necessary directories.
#squid –z
Add the squid daemon to auto-startup, on a Debian machine the command is: 
#update-rc.d  squid defaults
Start squid
#/etc/init.d/squid start

Suggestion:
Test squid without authentication first. If this works go to the next step.
To test without authentication, comment all of the parameters in the Authentication section by adding the “#” sign at the beginning of line and restart squid.

Add or remove daemons to autostart
cd /etc/init.d/
update-rc.d  winbind defaults
update-rc.d -f apache2 remove

Tweaking performance on SQUID

A few settings that can dramaticaly improve the performance on your proxy:

cache_dir ufs /var/spool/squid 1000 50 256
This is the default Squid storage type configuration.
Change the storage type from ufs to aufs if using a Linux or variants.
Change the storage type from ufs to diskd if using BSD or variants.
If you use Windows, is probably for testing purposes, or because you don’t have a machine. Once the testing is done change to Linux or BSD.
The numeric parameters are:
First parameter is the amount of disk space in Mbytes to be used by Squid. The more you use the more physical memory (RAM) you need for indexes in order to be effective.
The rule is that you need
If you want to use the whole drive’s, (partition), space make sure you subtract 20% and use that value. In other words you can only use 80% of the drive.
The second and third parameters are the number of first and second level subdirectories that are created.

cache_mem 64 MB
The more memory you have the better it performs. Local, (cached), objects are much faster to retrieve than external ones.
The more local objects you can store the faster Squid responds.
Squid uses cache for many things other than memory cache, so make sure you have enough memory left when you configure cache_mem.

Memory cache is better for speed than disk, but is lost more easily and you can get bigger cache total spending RAM on indexes.

maximum_object_size 20480 KB
Today’s Internet usage contains has a lot of traffic in the 2MB to 200MB range. This traffic is comprised of multimedia objects, update files, etc.
You need to investigate your traffic and see what is a good number for you.

maximum_object_size_in_memory 64 KB
If you have little memory keep the default 8 KB. It is better to serve more fast pages from memory than a few slow pages that will run faster.

Check if your proxy works and if is logging properly the access.
On your proxy machine run the following command to see realtime access on the proxy: tail -f /var/log/squid/access.log On a client computer open the browser of your choice and change Networking options so that the browser uses the newly installed proxy.
Start to browse and look on the proxy’s console to see your activity logged.