I am not able to add add-ins in my PowerPoint due to following error

Hi,

How did you add the add-in in PowerPoint?

Did you mean the third part add-in for PowerPoint or Add-in program in ribbon?

What version of Office did you use? I suggest you go to File- Account and provide the detail version number here:

Please refer to this support article and check if it helps:

https://support.microsoft.com/en-us/office/add-or-load-a-powerpoint-add-in-3de8bbc2-2481-457a-8841-7334cd5b455f

Please be a bit more precise to explain your problem or you can upload a screenshot so that I can get more accurate solutions to this problem. I’m glad to help and follow up your reply.

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I was referring to the Ribbon add-in program, which allows us to add add-ins from the office store. The following image has all the information you needed.