GAMS Support

How to install your GAMS license

The most common question we receive is how to install the GAMS license file correctly. If you have purchased GAMS, then you will have received an email with the license information. If you just want to give GAMS a try, you have to create a free demo license for yourself on our download page . You will then receive an automated email with your demo license information. Once you have that information, you can follow the steps shown in the video below:

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Technical Support

In case of other technical problems please contact the GAMS support at .

To speed up the process, please provide the following information:

  • The GAMS Distribution and the solver you are using.
  • Your GAMS license-id (DC.. in the fifth line of your GAMS license file). See example below:
  • The platform you are working on (Windows, macOS, Linux, 32 or 64 bit)
  • A copy of the GAMS log and lst file.
  • Any other information that may help us to reproduce the problem, for example a (compressed) GAMS file.
  • In case there are confidential issues, you may send us a scalar version of your model, click here for further instructions .
  • If requested, we are happy to sign a non-disclosure agreement (NDA), also known as a confidentiality agreement (CA).

How to send files

Via email

Our e-mail system can handle attachments up to a size of 20MB and does not accept executable files (such as files ending in .exe, bat, ps, or cmd), even if they are sent in a zipped (.zip, .tar, .tgz, .taz, .z, .gz) format. Any message of this type sent to us will be bounced back you. Adding an underscore to the file attachment (e.g. file.zip_) will help.

Using our upload facility

If you want to send us a larger file you can use our upload facility. Make sure to send an accompanying email to to let us know what you sent.

In general we will get back to you within 8 business hours. In case you do not receive a reply within 16 business hours then please see our contact page for alternative ways of contacting us.