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.
Questions tagged [checksum]
148 questions
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votes
31 answers
Is there a built-in checksum utility on Windows 7?
Is there a built-in checksum/hash utility on Windows 7?
user64996
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Does an identical cryptographic hash or checksum for two files mean they are identical?
I have 2 excel documents and I want to check if they are exactly the same, apart from the file name.
For example, the files are called fileone.xls and filetwo.xls. Apart from the file names, their contents are presumed to be identical but this is…
sam
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Does compiling a program twice 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 the checksum fail?
If so, why is this? If not,…
David
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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 website, so I am having to find 3rd party copies.
user66001
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Why do I get different results from Mac's shasum than from other shasum calculators?
I'm entering:
appletree:~ somename$ shasum -a 512 <<< test
And the output is:
0e3e75234abc68f4378a86b3f4b32a198ba301845b0cd6e50106e874345700cc6663a86c1ea125dc5e92be17c98f9a0f85ca9d5f595db2012f7cc3571945c123 -
Then I go to some online hash…
peter_the_oak
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How to generate MD5 hash value for multiple files in a folder using cmd
As mentioned in this page,
the command:CertUtil -hashfile yourFileName MD5can be used
to obtain the MD5 hash value for a particular file.
How can I find the MD5 hash values for multiple files in a folder using cmd?
Hari
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Do we really need to check the integrity of downloaded files?
I downloaded a huge amount of files, but discovered the use of md5 and sha as integrity checkers quite recently. From then I always prefer to check it for big downloaded files, even if I never found them to be corrupted.
Do we really need to check…
maxpesa
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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 signed.)
From the putty download page:
MD5: …
Elliptical view
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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 (copy, move, etc.) by calculating CRCs. Does Windows…
bwDraco
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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 disks after the copy, and they were all correct.
I…
Somebody still uses you MS-DOS
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What are these Google SHA1 images?
If you look at this page you'll see an monochrome image.
Above it says
Tip: Use the SHA1 checksum shown to verify file integrity.
However, I don't know if that's related. What are these things?
user3109
8
votes
3 answers
Sha256 checksum on terminal displaying strange characters
I've installed the hashalot first to use the sha256. Then something strange happened when using the command + filename:
mlockall: Cannot allocate memory
Warning: couldn't lock memory, are you root?
Enter passphrase:
I've never needed to enter…
anon
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how to verify whether a compressed .gz is corrupted or not?
I have many gz downloaded from the internet, and I would like to make sure they are not corrupted.
Does the fact that I can open the archive with winzip on windows proves that everything is fine?
I must find a way to check their integrity without…
ℕʘʘḆḽḘ
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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 generate the said checksum?
I will be copying a…
PoorLuzer
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What is the best way to make Calculate SHA1 as a context menu option in Mac OS X?
In order to calculate the SHA1 checksum of a downloaded file, I could type
/usr/bin/openssl sha1
in Terminal and then drag there the file which I want check. To make it simpler, one could enable a Context Menu item for this action.
What is the best…
Andrei
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