GAMS tests the distributions that can be found from the GAMS website, www.gams.com, that they are free of viruses. So far, all suspicious file alerts from virus scanners have been false alerts, i.e. false positives.
In most cases, problems caused by an interfering virus scanner can be resolved by disabling the live check of the virus scanner for the GAMS system directory (problem during installation of GAMS) or the corresponding project directory (problem during execution of GAMS).
The steps below describe how to verify that the downloaded GAMS file has not been tampered and give further information on how to send files for analysis to virus scanner providers.
A smart virus scanner can analyze the files inside the GAMS distribution file, i.e. installation file, however, it may or may not be true for all virus scanners. In case your virus scanner finds a suspicious file after you have already been working with GAMS for some time, then it is in general impossible to determine the origin of the suspicious file. Hence, in this case we recommend to uninstall GAMS and delete the GAMS System folder. However, please remember to keep a backup of your GAMS license file, gamslice.txt. Afterwards, you may install GAMS again, as well as, take in consideration the below steps.
You can compare the MD5-Hash values on the download website, with the values obtained from a program that calculates the MD5-Hash value of a file. If you are using Windows, then you may use the File Checksum Integrity Verifier Utility provided by Microsoft. On a Mac a tool is most likely included in the distribution. On a Linux, you may need to download a tool like md5sum. For more information see, for example, Wikipedia. The below statement shows the output when testing some utilities that calculates the MD5-Hash values for GAMS 24.3.3 distribution file on different platforms:
Windows Command Prompt statement:
fciv.exe windows_x64_64.exe // // File Checksum Integrity Verifier version 2.05. // ec2b8c7d3229f3efacba5500d33c5bed windows_x64_64.exe
Mac Terminal Window statement:
md5 osx_x64_64_sfx.exe MD5 (osx_x64_64_sfx.exe) = 82412b4c4a0cb362417c468a229f166a
Linux Shell statement:
md5sum linux_x64_64_sfx.exe e1b166d9343bde374d86b13172465ec9 linux_x64_64_sfx.exe
Once you verified that the downloaded GAMS file has not been tampered, you may disable the live check of the virus scanner for the GAMS system directory (problem during installation of GAMS) or the corresponding project directory (problem during execution of GAMS).
In case you successfully completed step 2 but want to scan your GAMS distribution with a virus scanner anyway, we suggest to first run the virus scanner on the GAMS distribution file. If no viruses are found, then install (extract) GAMS and run the virus scanner on the installed files, i.e. GAMS System folder e.g. “C:\GAMS\win64\24.8.2” .
Most virus scanner providers offer a way to send suspicious files to be analyzed. If your virus scanner finds a suspicious file from the GAMS distribution file, then please report this issue directly to your anti-virus provider. If no suspicious files are found, then you can continue and install (extract) GAMS and run the virus scanner on extracted files, i.e. GAMS System folder. If a suspicious file is found, report the issue and if not, then it seems like the GAMS System is free of viruses.
Note that, many anti-virus software providers have an internal system for sending files for analyses. Below you can find links to some Anti-Virus providers websites, where you can upload suspicious files for analysis:
We are confident that our software does not contain viruses and so far, all suspicious file alerts have been false alerts, i.e. false positives. However, to be on the safe said, you may wait until you hear from your anti-virus provider that the suspicious file is a false positive.