Thanks for your comment, and for taking the time to reach out. I have added the constants above to the https://opensolver.org/opensolver-api-reference/ page. Andrew

Public Enum RelationConsts
RelationLE = 1
RelationEQ = 2
RelationGE = 3
RelationINT = 4
RelationBIN = 5
RelationAllDiff = 6

It works!
Enabling ControlX in Excel’s security option solved the RefEdit problem.
Many thanks Andrew.

If all the RefEdit controls have gone, then it is probably because of a recent update to Excel in which ActiveX controls (including RefEdit) are now turned off by default. Microsoft make these changes occasionally. Please see https://opensolver.org/help/#refedit for more information on this. Because this is a new issue for us, we would love to know if you are able to get OpenSolver working. Thanks, Andrew

Further information:
OpenSolver Version 2.9.4 (2021.01.15) running on 64-bit Windows 10.0 with VBA7 in 64-bit Excel 16.0
Microsoft 365
Thank you in advance for your help.

Thanks for your query. A few comments.
1) Make sure you copy the folders over as well as the OpenSolver Excel file. Your users will need to be able to run the .exe files for OpenSolver to work. Some newer Mircosoft tools block Office Apps from running .exe files, so you will need to add exceptions if this is the case in your systems.
2) I personally do not set up OpenSolver to autoload. I find it easier to load it when I need it. I just pin it to my recent files within the Excel open dialog.
3) If you really want OpenSolver to autoload, then you either need to put it into a special folder (which the MS documentation should know about; it has changed over the years), or set a registry entry. The About OpenSolver dialog will let you set this registry entry (and you can look at the OpenSolver VBA code to find which registry setting it is; I don’t remember, sorry.)
Hope this helps,
Andrew

I’m planning to deploy OpenSolver using a PowerShell script through MECM, our standard deployment tool.

My main concern is whether there is a way to automate the load behavior of OpenSolver. Ideally, we would like OpenSolver to be available automatically when users open Excel.

Is there a registry key or configuration file we can use to manage the load behavior of this Excel add-in?

I look forward to your guidance. Thank you!

Did you mark the .zip file as safe before you extracted the files as detailed in the download instructions? It must be possible to open .xlsm files in every iteration of Excel; that is a core Excel capability. Andrew

Thanks

You need to create a cell containing SUM(A1:C1) and apply the limit of 5 to this using a constraint. Andrew