MD5 (Message-Digest algorithm 5) is a widely used cryptographic hash function with a 128-bit hash value to provide some assurance that a transferred file has arrived intact. You can compare the checksum of a downloaded file, say masterkey-linux-0.1.iso to our pre-computed one stored in a md5 file masterkey-linux-0.1.iso.md5. Generally speaking, if these two hash vaules match, the file you downloaded is identical to the one released on the web site.

To verify the md5 checksum of a downloaded file (i.e., masterkey-linux-0.1.iso) under Windows, you need also download its md5 file in which the pre-computed checksum is stored (i.e., masterkey-linux-0.1.iso.md5) and a MD5 generating and verifying tool such as MD5summer. The file to be checked and its md5 file MUST be stored in the same folder.

• Download Latest version 1.2.0.5 of MD5summer from http://www.md5summer.org/, md5v12005.zip;
• Unzip the compressed ZIP file to a folder, say: C:\md5summer;
• Nevigate to the md5summer foler, and run MD5summer by click the icon of md5summer.exe as shown below:

• Select the folder which stores related files (G:\distribution in this example);

• Select the md5 file, say masterkey-linux-0.1.iso.md5, click Open;

• MD5summer will generate a md5 hash (checksum) for the file (masterkey-linux-0.1.iso) defined in the md5 file (masterkey-linux-0.1.iso.md5) and compare the newly generated md5 checksum with the one stored in the md5 file.

• If you see a green ball placed against the filename, it means the two checksums match and the file you downloaded is identical to the one released on our web site as shown below.