File checksum

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NoTouch Desktop uses potentially large files of different file types. To ensure file integrity, several checks are used:

  • File size in bytes
  • MD5 checksum
  • SHA1 checksum

All these values are shown in the NComputing download portal, and to be sure your file is ok, you should check your local file at least for file size and one of the two checksums, MD5 or SHA1.

If a download ends prematurely, in most cases the file size will be smaller than on the NComputing server. However, it is still possible for a file to be corrupt and have the same file size. File size alone does not indicate a "good" file. It can only indicate a problem - if it differs -, but not the other way round.

Check MD5 and SHA1 on Windows

Microsoft Windows does not bring a file checksum utility by default. However, several alternatives exist:

  • Microsoft FCIV [1] and a tutorial on how to use it [2]
  • MD5sum for Windows [3]
  • SHA1sum for Windows [4]

NComputing assumes no liability for these external links!

Check MD5 and SHA1 on Mac OS

Mac OS X brings MD5 and SHA1 programs by default. Open a "Terminal" and enter these commands: 

   cd Downloads
   md5 FILE_TO_TEST.xxx

or 

   cd Downloads
   shasum FILE_TO_TEST.xxx

Of course you need to replace FILE_TO_TEST.xxx with the actual filename.

Check MD5 and SHA1 on Linux

All desktop Linux distributions bring MD5 and SHA1 programs by default. Open a "Terminal" (xterm/rxvt/SSH login) and enter these commands: 

   md5sum /path/FILE_TO_TEST.xxx

or 

   sha1sum /path/FILE_TO_TEST.xxx

Of course you need to replace FILE_TO_TEST.xxx with the actual filename, and path referring to the path where the file is located (depending on Linux distribution).