AIMMS Knowledge Base Article – KB000057

AIMMS Launcher: how does it choose an AIMMS version?

The information in this article applies to:

  • AIMMS Launcher, all versions


When you double-click on an AIMMS project file in Windows, the AIMMS launcher will determine with which version of AIMMS this project will be opened. The launcher will try to find the closest match to open the project.


First, the launcher determines whether the project is an ASCII project or a Unicode project, because you can not open an ASCII project with a Unicode AIMMS and vice versa. The rest of the process description below only considers the installed AIMMS versions of the same type (i.e. either ASCII or Unicode).

When a project is created with 3.X, the launcher will first look whether AIMMS 3.X is installed. If the project was created with the 64-bit version of AIMMS, preference will be given to the 64-bit version of AIMMS in case both the 32- and 64-bit version of 3.X are installed. If no matching version is found this way, the launcher will try to look for any installed (32-/64-bit, again with a preference for 64-bit in case the project was created with a 64-bit version of AIMMS) version of the AIMMS Viewer version of 3.X.

If no exact version match can be found (i.e. a 3.X version of either AIMMS or the AIMMS Viewer), then the launcher will look for a 3.Y version with Y > X. The steps here are similar to the ones when searching for an exact match: if there is an AIMMS 3.Y installed, this will be used (and again, if you have both 32- and 64-bit version of 3.Y installed, it will give preference to 64-bit if the project was created with a 64-bit version of AIMMS). If multiple different versions Y and Y’ are found, the launcher will use the one closest to the original X. If no 3.Y AIMMS can be found, then the launcher will start to look for a 3.Y version of the AIMMS Viewer.


  • Project created with Unicode AIMMS 3.8
  • End User has ASCII AIMMS 3.8, Unicode AIMMS 3.10, Unicode AIMMS Viewer 3.9

The exact version match 3.8 will not be used, because it is not Unicode. Though the Viewer version is a closer match (3.9 versus 3.10), the launcher will use the Unicode version of AIMMS 3.10, because it gives preference to the regular AIMMS over the Viewer when looking for a version > 3.8. If this end-user would have the Unicode 3.8 Viewer installed as well, the launcher would use this 3.8 Unicode Viewer to open the project, because this would be an exact version match. 


Last reviewed: 21-05-2010
Keywords: KB000057, Launcher