About checksum files

 

Checksum is a short data sequence which is mathematically generated from a file. Store separately the checksum and the file for a while. Later you take your file again, and want to know whether it is intact and unharmed. Generate the checksum again from the file, take the old checksum and compare them. If they are identical then we can say that the file has not been changed. There is only a very very narrow possibility of still having a corrupted data bit in the file and that remains undetected.

You could store a copy of the file itself at the other place but the checksum is much smaller. But this does not mean that you might cease archiving your precious files again and again! The checksum only marks the damage, not repairs.

If you receive the distribution package of our program from somebody else, it is possible that the files are already infected with a malware, or something nasty was built in.

We support you to verify the installer files before starting that, avoiding this way the intrusion of unwanted things into your system.

Download any of the offered checksum files (SFV or MD5, as you like) from the download page of the software you choosed, and apply it. These files contain the checksums for each files of the package. Never use checksum files from any other source than this site because that can be easily adjusted to the modified content!

How to apply? There are several programs for that, we recommend two of them: the portable and very handy SFV Ninja or the famous Total Commander. They are capable to handle both SFV (CRC32) and MD5 checksum files.

Well, maybe you have never done anything like this before. The following guide is made just for you.

There are main files in the package, and there are secondary files. The latter ones are file_id.diz, file_id.png and readme.txt. If these and only these documentation files are modified then somebody changed them but the installation package is clean, you can run Setup.exe. Be careful.

 
 

 

  

 

Applying checksum file for SFV Ninja

Download distribution package of the program. Unpack that into a folder. Download any of the checksum files from the page of the package. (Click on images for real size.)
      

 

    


Put the checksum file into the folder mentioned before.
      

      

Open SFV Ninja.
      		      

Click on File menu, Load checksum file command, and select the checksum file. The files which are included in the checksum file will be listed immediately. If the table remains empty, something was done wrong. The checksum file has to be placed and selected in the folder of the unpacked installer files.
      		      

Set the type of the file (SFV or MD5) in Mode list, above right. Then click on All button on tool bar.
      		      


The checking procedure is very short. Look at the result at the bottom line of the window. If not each file is OK then the package is modified, not unharmed. See our note about the secondary files, in the introduction. Try to load it again from our site, or send us an e-mail about the problem. See Contact.
      

      

 

Applying checksum file for Total Commander

Download distribution package of the program. Unpack that into a folder. Download any of the checksum files from the page of the package. (Click on images for real size.)
      

      

Put the checksum file into the folder mentioned before.
      

      

Move the cursor or click to that file.
      		      

Select the File menu, Verify CRC Checksums command. Also do this if the checksum file is the MD5 type.
      		      


The checking procedure runs very quickly. Look at the result in the window. If not each file is OK then the package is modified, not unharmed. See our note about the secondary files, in the introduction. Try to load it again from our site, or send us an e-mail about the problem. See Contact.