A checksum is a value created from a binary file that can be used to validate its authenticity and integrity. An example of a checksum is MD4, MD5 and SHA-1.

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Why do repeated downloads for Google Chrome setup have each time different hashes?

I've tried downloading the setup files for a standalone offline installation version several times in rapid succession. Each next file has an identical size but a different hash. Why is that? Do they ...
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0answers
26 views

CRC Download Errors

I am using a DSL 3Mbit line from my service provider *. I connect to it with a WLAN router. Recently I get a whole lot of CRC errors when I am downloading (For instance when using JDownloader but ...
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2answers
32 views

File integrity checking

I have a lot of PDFs and many of them may be corrupt. Rather than checking each one, how could I check them all at once and delete any that are corrupt? Using Linux. I also don't have a way to get ...
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3answers
51 views

Extract identical files from two directories

I am looking for a linux solution for the following problem: Given two directories with a large number of files. All file names are random and different in both directories. The contents of some of ...
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1answer
303 views

Rename files by md5 checksum

What program can I use to rename files with their calculated md5 checksums? GUI or CLI Programs for Linux or Windows or scripts for DOS or the Linux terminal.
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1answer
654 views

Windows 8.1 Checksum

I've looked all over for the sha-1 or sha-256 checksum for the windows 8.1 iso that you get with the Microsoft’s “Upgrade Windows with only a product key” page but none of the check sums provided on ...
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1answer
331 views

How does one verify the PGP RSA and/or DSA checksum signatures for putty?

To verify the download integrity of putty, how is the best way to first verify the "SHA-512: (RSA sig) | (DSA sig)" PGP signature of these check-sum files for putty? (I am guessing "sig" means ...
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1answer
2k views

Microsoft Windows ISO checksums

Is there an official source for Windows ISO (XP+) checksums, online? Wanting to download some older Windows versions, for support purposes, but they don't appear to be available on Microsoft's ...
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1answer
109 views

Checksums don't match is that bad?

I recently started looking at VisualStudio 2012. I tried downloading it from the official Microsoft link but it failed with some errors. As of some suggestions I downloaded the DVD5 ISO image to ...
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1answer
159 views

Is it possible to recalculate the system configuration checksum on a Cisco RV180W

My Cisco RV180W has a corrupt configuration which is breaking the user interface in a few places. After a factory reset, it's fine - but if I restore my previous configuration it breaks again. The ...
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5answers
834 views

Does recompiling a program produce a bit-for-bit identical binary?

If I were to compile a program into a single binary, make a checksum, and then recompile it on the same machine with the same compiler and compiler settings and checksum the recompiled program, would ...
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0answers
16 views

Video upload checksums not matching

We have a setup that takes a small quantity of small video uploads directly from people's mobile phones using apps, onto a small VPS. It rejects them if the MD5 checksum on the phone doesn't match the ...
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3answers
264 views

How do I verify the authenticity of a linux system executable?

I'm aware of md5sum and gpg but I have no idea if there are recorded checksums for whatever current version of ubuntu is installed. Do these get recorded somewhere? Specifically I'm suspicious that ...
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1answer
3k views

How is TCP/UDP checksum working?

I used raw socket to create some UDP packets and then send them to a UDP server I notice that when I put a wrong UDP checksum number the UDP server doesn't accept it, but if I put all 0 on the ...
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1answer
601 views

Does Windows calculate CRCs to check every file operation?

When Windows encounters a file corruption on a file system, it may return the following error message: Data error (cyclic redundancy check). This suggests Windows checks every file operation ...
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1answer
96 views

File corruption detection strategy

due to current high price of hdds, I would like to switch from running RAID1 to JBOD + offsite backup (Backblaze). In theory it's a much better approach (if PC gets fried by lighting strike, I still ...
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1answer
636 views

How to get rid of UDP checksum error messages in virtual console?

Whenever I am streaming a video in the web browser, while connected to my school LAN via ethernet, and switch to the virtual console (ctrl-alt-f1) on Ubuntu, I get an error that looks like the ...
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2answers
446 views

Calculate checksum of file from right-click menu? [duplicate]

Possible Duplicate: Looking for MD5 utility that integrates to Windows What would be the easiest way to have the checksum of a file shown in a message box using the right click menu on the ...
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0answers
121 views

Window Vista cannot create new folder, note, etc when right click and recent items forever empty after crashes

Basically my computer crashes and after I reboot I got a checksum error, so I reboot again and these problems appears: 1):Unable to create new folder, notes, zip file,etc. (when I right click in ...
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2answers
146 views

how to backup only files paths, names, sizes and checksums?

I'm looking for an application which will allow me to select some folders, and then regularly backup only complete paths, names, sizes and checksums of the files within those folders and their ...
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1answer
1k views

File copy program that generates checksums of the data while copying too

My question in short: is there a tool that copies a file from directory A to B while, simultaneously, generating the checksum of the file it has copied/read, without doing an extra read/pass just to ...
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0answers
82 views

MD5 for Git's git-credential-osxkeychain executable? [closed]

I'm setting up a GitHub account and have downloaded Git's credential-osxkeychain executable via the Password Caching section of GitHub's instructions. But... I am paranoid enough to look for some ...
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2answers
3k views

“CMOS check sum error” while booting

I am using an HCL desktop system (Core 2 Duo, 1 GB RAM, Windows XP SP2). While booting I got the following message. CMOS check sum error. Press f1 to continue When pressing F1 it is working ...
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0answers
82 views

Cannot open an encrypted file on OS X

I cannot decrypt files on OS X (10.6.8 and 10.8.2) which I have encrypted on Ubuntu (10.04) using ccrypt. As a similar problem, I have a password file created with KeePassX. I just cannot open it on ...
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1answer
113 views

Can I rely on CDs and DVDs for storage when I copy them without errors?

I have old CD and DVDs. I am copying the files I have on these discs to my hard drive, but can I be sure that these files are not broken? I copy these files with no errors and don't want to keep the ...
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1answer
1k views

recursive file/directory verification on linux

What would be a command structure or simple bash script to run to compare all files in one directory with all files in another directory, verifying their data are identical, or not, down to the bit? ...
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2answers
1k views

How do downloads become corrupt? (SHA1 value varies)

I downloaded VS 2012 using IDM. While I did pause and resume several times, it downloaded successfully. BUT, the SHA1 and CRC values do not match with the given values in the website. This means that ...
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2answers
2k views

Is it possible to download corrupted torrent files, even with a download client builtin checksum verification?

I downloaded some mkv/mp4 files with my new router (I can download directly from it, using transmission), and all of them seem to be corrupted: lags, strange artifacts when using vlc, crashes with ...
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2answers
343 views

How to do checksum on web hosting site?

I am having problems uploading a large file to a web site. When the file is subsequently downloaded it is corrupt. How can I do a checksum of the file while it is on the web site so I don't have ...
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1answer
421 views

Is there a utility to verify the checksums of every Windows file?

I would like to know if there is a utility to verify the checksums of every Windows file on my Windows 7 Ultimate system. It seems on the surface such an obvious utility but I don't ever remember ...
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1answer
160 views

sourceforge checksums: Where are they? [closed]

I've been particular about checksumming all downloaded software. Today, trying to download from Sourceforge, I could not find any checksums for the projects. Am I just missing them or are they not ...
0
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1answer
181 views

Where can I find checksums for the GlassFish Server 3.1.1 Open Source Edition Full Platform zip file?

I've downloaded the Glassfish zip file from http://glassfish.java.net/downloads/3.1.1-final.html and I'd like to verify the integrity of the file, but I can't find any checksums. Where can they be ...
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3answers
1k views

How does a downloaded ISO get corrupted? [duplicate]

Possible Duplicate: Is it possible to get corrupted download with http? I downloaded an ISO for fedora. Went to install it as a VM. It failed 5 times the installer. The warning for the ...
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1answer
227 views

Tool to maintain/keep track of filesystem content integrity?

I'm looking for a tool to maintain the integrity of a filesystem and it's contents using checksums. Effectively storing a list of checksums/filename pairs somewhere on the filesystem in a way that can ...
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3answers
243 views

How do I check the checksum of a download and why should I?

My memory isn't great but I think five or six years ago, when I downloaded some package, there was never a checksum line under the download icon on the webpage. And no instructions to "check the ...
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2answers
3k views

Checksumming an entire CD/DVD

I'm publishing a set of documentation to be delivered on CD. My Company's European production manager is concerned that he has no way to verify that the data on the discs he produces is correct. He ...
2
votes
1answer
75 views

Backup solution: hash/checksumming and/or error correction

I'm trying to keep my data well protected with backups, using multiple hard drives (basically swapping the backup disk out every week). For checking validity, I was originally planning on md5summing ...
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6answers
214 views

Checksum for Protecting Read-Only Documents

My father owns a small business and has to hand over several year's worth of financial documents to his insurance's auditor. He's asked me to go through and make sure everything is "read-only" so the ...
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votes
2answers
1k views

Is verifying a MD5 sum after copying 100GB of data safe?

I'm copying 100GB from a Windows 7 workstation to 2 external drives (if you have only one backup, then you have none). All files have a MD5 checksum. I've verified all MD5 checksums on the external ...
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3answers
937 views

Solution for noisy network that corrupts downloaded files

The network on the company where my wife works sucks BIG TIME. Almost every single file bigger then a few hundred kB is corrupted during download and even web pages are sometimes garbled. We checked ...
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votes
2answers
685 views

Verification of files on backup media - after the backup

I have a system in place where I back up my work files daily to a portable hard drive. I actually have two portable hard drives - one is stored off-site and I swap them regularly. I also keep my ...
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1answer
818 views

KDE on Windows won't download/install

No matter which mirror I use, I get this error. I've tried a few times over the last several weeks. Download failed --------------------------- The download of ...
0
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1answer
63 views

How can I locate the header + object file of cksum in Mac OS X

I'm trying to locate the header + object file of cksum in Mac OS X, but with no lack. Any suggestions?
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1answer
86 views

What does my computer do if it receives a data-packet with a wrong checksum?

Since modern routers don't check the header-checksum any more to increase performance I'm wondering what my computer is doing with defective data-packets? Further reading links appreciated.
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3answers
3k views

How can I copy files to an external drive and verify their integrity in OS X?

I'm moving large amounts of data from one external drive to another larger one. The files are important and the smaller drives need to be cleared and reused (HD camera). Is there some utility for ...
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votes
1answer
138 views

What type of malware can reside in windows restore?

I was reading aking1012's comment on How to create Windows Vista/Windows 7 Startup disk or Rescue disk or system restore points on a CD? . He says that: The first thing I usually do is disable ...
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2answers
622 views

Which backup apps verify the checksum of what they've written?

I've been using TeraCopy and DirSyncPro for moving & syncing large file sets (1.5TB) between 3 locations- a SMB NAS share, a local drive & an external. Neither of these solutions are quite ...
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1answer
206 views

Hardware digital signature

Is it possible to show how generate a digital signature, a checksum, or something along those lines based on your computer hardware using an Ubuntu Live CD? So, once the first digital signature is ...
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2answers
2k views

Looking for OS X utility to verify/validate copied files/directories - checksum / SFV / MD5

Looking for the best way to easily validate the integrity of files/folder in OS X when copied from one location to another. I've downloaded SuperSFV but it appears to be very slow. Also new to the ...
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3answers
287 views

tool for maintain incrementally the checksum of a large set of files

I need a tool to generate and maintain the checksum (MD5, SHA1, it does not matter) of all files in a folder or a set of folders, recursively. Sometimes I will add/update/remove some files and I ...