When downloading any large file, you are usually offered a hash comparison to validate the download. While this is common practice in the UNIX and Linux world, Windows administrators may be a little unfamiliar with the process. The good news is we can do it quite easily in Windows.

For MD5 checks, I use a free tool called HashTab, which allows you to do comparisons via a right-click on Windows platforms. HashTab supports the major cryptology hash types: MD5, SHA1, and CRC-32. Once installed on Windows Servers, HashTab will appear when you right-click a file. The data will undergo the hash process and give a result. When you download a file that provides a hash, you can compare the file, as shown in the example of a successful comparison in Figure A.
Figure A

Larger files will take a moment to compute the hash for comparison; large .ISO files will only take a few seconds. Likewise, with HashTab, you can create MD5, SHA1, or CRC-32 hashes for large files that you distribute. MD5 and SHA1 are the more popular hash types and are usually displayed in the following format:

(md5sum:d52a89ad7eb3d773797afb2059916b29)
(sha1sum:5b54a457249051ca63e94dc26abb7fe87d75ec4e)

With HashTab, providing hashes for your server content available for download can ensure the accuracy of transfer for larger files.

In the discussion, let us know which tools you use to verify file hashes and share your thoughts about file hashing practices.

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