OpenSolver is updated whenever new features are added or bugs fixed. Please check out the blog page for release details. You can also use the built-in update checker to keep up-to-date with the latest release.
OpenSolver comes in two versions, a simpler “linear” version and an “advanced” version with support for more solvers. Both versions are available for Mac and Windows. On Windows, OpenSolver should work with Excel 2007 and later; we test it on 32 and 64 bit Windows in Excel 2010 and 2013. (Older versions worked with Excel 2003, but we don’t test this any more.) On Mac OS X, it should work using Excel for Mac 2011 with any version of OS X newer than 10.7.
OpenSolver currently does not work on Excel 2016 for Mac. Users have reported that OpenSolver works on both Windows 10 and Excel 2016 for Windows. We haven’t extensively tested these yet, so let us know how it goes.
Office July 2016 Security Update Microsoft updated the security requirements for add-ins in July 2016. You now need to “Unblock” the .zip file before extracting the files; please see the instructions below and this help item.
OpenSolver Linear: This is the simpler version that solves linear models using the COIN-OR CBC optimization engine, with the option of using Gurobi if you have a license. Most people use this version.
OpenSolver Advanced: As well as the linear solvers, this version includes various non-linear solvers and support for solving models in the cloud using NEOS; more info is here. Much of this code is still new and experimental, and so may not work for you.
You can see all our downloads, including previous versions, on our Open Solver Source Forge site.
To download and use OpenSolver:
- Download the OpenSolver Linear zip file (either Mac or Windows, depending on the machine you are using). You can also try out our experimental Advanced release (Windows or Mac) for access to non-linear solvers. As noted above, OpenSolver does not work on Excel 2016 for Mac.
- Right click the downloaded zip file, choose Properties, and click the “Unblock” button. If you don’t see this button, you can skip this step. (This step is a new requirement following a July 2016 update to Excel.)
Close the Properties window.
- Extract the files to a convenient location. (All files and sub-folders, including OpenSolver.xlam, must stay together; please do not move any files or folders out of the unzipped OpenSolver folder.) OpenSolver on Windows may not work if installed to an unmapped directory such as \\server\myfiles\ or one that contains unicode characters.
- Double click on OpenSolver.xlam. There may then be a small wait as Excel checks the digital signature on the OpenSolver code.
- If asked in an Excel Security Notice, give Excel permissions to enable the OpenSolver macros. You can click Trust all from Publisher if you do not want to be shown the Excel Security Notice again.
- The OpenSolver commands will then appear under Excel’s Data tab on Windows, or in the Menu Bar on a Mac.
Note that as of October 2014, the OpenSolver code is signed by the publisher “The University of Auckland”. This makes the code more secure. However, Excel will occasionally need to check the digital signature by contacting servers online, which can take a few seconds.
OpenSolver will be available until you quit Excel. If you wish, there are two ways you can make OpenSolver permanently available in Excel. Either, use OpenSolver… About OpenSolver…. and check “Load OpenSolver when Excel starts”. Alternatively, you can copy the files from the .zip into the Excel add-in directory. This is typically:
C:\Documents and Settings\"user name"\Application Data\Microsoft\Addins
Windows Vista and later (7, 8, 8.1):
/Applications/Microsoft Office 2011/Office/Add-Ins
The Excel Solver is a product developed by Frontline Systems for Microsoft. OpenSolver has no affiliation with, nor is recommended by, Microsoft or Frontline Systems. All trademark terms are the property of their respective owners.