A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
Hi @Oscar Chapa,
Thanks for sharing the error details this helps narrow things down. To point you in the right direction, could you clarify a few things?
- Where are you installing from? Are you trying to add it via the direct Microsoft Marketplace webpage/link, or from inside Excel itself (Home/Insert > Add-ins > Get Add-ins)?
- Which listing are you selecting? Are you searching for "Claude for Microsoft 365," or an older/separate "Claude for Excel" listing?
- What Excel for Mac version are you on? (Excel > About Microsoft Excel). Claude for Excel requires 16.46+ (build 21011600+).
- Does this happen with other add-ins too? Try installing any other free add-in (e.g., from More Add-ins) if that also fails with the same "catalog"/certificate-style error, it points to an account/catalog issue rather than something Claude-specific.
- Browser/network: Have you tried a private/incognito browser window, signed out of other Microsoft accounts, or a different network?
In the meantime please try Install from inside Excel rather than the Marketplace webpage/browser link open Excel > Home (or Insert) > Add-ins > Get Add-ins/More Add-ins, then search for "Claude for Microsoft 365" and select Add. This uses a different install path than the direct Marketplace URL and often bypasses the error.
Thank you again for your time and understanding. I really appreciate your patience, and I'm here to help. Looking forward to your response.
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