Below, on this page, you can download and installe stable versions. For the interested users, development versions and source code is available here:

• Development versions
• Source code
  

In order to install, first close Gekko. Then uninstall your existing Gekko version (Control panel --> Programs and features --> Uninstall a program). Finally, download and run the installer file (see below: InstallerForGekko.msi). Problems: see the problem-shooting guide. 

During installation, you can safely ignore this warning if it appears:

• Stable version 2.0 (patch #3)-- 2/3 2016
• All the versions in the 2.0 series are considered stable, i.e. the patches do not alter critical code (the full version number is 2.0.3).
  
• Installer file (please close Gekko before installation!)
• Setup file (only relevant if you have problems with the installer file)
• Zip-file (for manual installation -- experts only!)
• Change-log (detailed list of changes)
• Stable version, with updated help files. Regarding what is new in Gekko 2.0, please consult the online help file (particularly here).
  
  • 2.0.3: Some smaller bugfixes + update of help-file index/keywords.
    
  • 2.0.2: Some bugfixes related to PRT/MULPRT.
  • 2.0.1: First version.
    

• Stable version 1.8 -- 22/10 2013
• All the versions in the 1.8 series are considered stable, i.e. the patches do not alter critical code (the full version number is 1.8.1).
  
• Installer file (please close Gekko before installation!)
• Setup file (only relevant if you have problems with the installer file)
• Zip-file (for manual installation -- experts only!)
• Change-log (detailed list of changes)
• Stable version, with updated help files.

• Stable version 1.6 (patch #8) -- 2/5 2013
• All the versions in the 1.6 series are considered stable, i.e. the patches do not alter critical code (the full version number is 1.6.8).
  
• Known BUGS in version 1.6.7 (fixed in 1.6.8)
  
• Installer file (please close Gekko before installation!)
• Setup file (only relevant if you have problems with the installer file)
• Zip-file (for manual installation -- experts only!)
• Change-log (detailed list of changes)
• Stable version, with updated help files.
  • 1.6.1: First version.
  • 1.6.2: Minor bugfixes.
  • 1.6.3: Minor fixes related to menus.
  • 1.6.4: Minor fixes related to menus.
    
  • 1.6.5: Minor fixes (table folders).
    
  • 1.6.6: Minor bugfixes.
  • 1.6.7: Bugfix related to failsafe mode.
  • 1.6.8: Bugfixes, primarily RETURN command.

• Stable version 1.4 (patch #9) -- 5/2 2012
• All the versions in the 1.4 series are considered stable, i.e. the patches do not alter critical code (the full version number is 1.4.9).
  
• Installer file (please close Gekko before installation!)
• Setup file (only relevant if you have problems with the installer file)
• Zip-file (for manual installation -- experts only!)
  
• Stable version, with updated help files.
  
• Patches:
  • 1.4.1: Fixes an issue when combining Newton and Gauss in fail-safe mode.
    
  • 1.4.2: Makes PPLOT and UDVALG windows truly independent/floating.
    
  • 1.4.3: Fixes error message line numbers + some minor problems.
    
  • 1.4.4: Adds error dialog, and commands PAUSE, STOP and EXIT.
    
  • 1.4.5: Has "CLEAR *", CLOSEBANKS, and some minor fixes.
    
  • 1.4.6: Minor sound option changes.
    
  • 1.4.7: Gauss convergence, ITERSHOW and CHECKOFF commands.
    
  • 1.4.8: Added option "reorder" for the Gauss solver.
  • 1.4.9: Checks for problems using '()' together with ';' in same line.

• Stable vrsion 1.2 -- 14/6 2011
• Installer file (please close Gekko before installation!)
• Setup file (only relevant if you have problems with the installer file)
• Mostly minor changes on top of version 1.0.53. The help files have been updated. This is a stable version, for use on the ADAM workshop Thursday/Friday 16/6 and 17/6 2011 (the full version number is 1.2.0). In the future, versions with an even digit after the first "." will indicate stable versions.