Google Workspace add-on using the wrong account?

If an add-on will not open, reports an authorization or storage error, or uses an unexpected account, try a window signed into only the Google account you want to use. Google says simultaneous sign-in to multiple accounts is unsupported for Apps Script add-ons and recommends a single-account session or private window in its troubleshooting guidance.

Open it with one account

1. Save your work. Open a Chrome Incognito window, or your browser’s equivalent private window.
2. Go to Google Drive and sign into only the account that installed and authorized the add-on. If you already paid, use the Google account associated with that purchase.
3. Open the spreadsheet or presentation there. Check the Google account menu in the file before reopening the add-on from Extensions. Complete Google’s authorization if it is requested.
4. Check the selected source and destination before starting. If a previous attempt might have written results, inspect those results before repeating it, especially when creating events or slides.

For regular use, a separate Chrome profile keeps work and personal sessions apart: choose Chrome’s profile menu, then Add Chrome profile. Keep just the intended Google account signed into that profile. Signing into a Google website is separate from Chrome’s optional browser sign-in and sync.

The file opens, but the add-on still fails

In our two-account tests, opening the file as the second account did not reliably make add-on calls use that account; Google also sometimes refused access to add-on storage. The account shown by the file alone is therefore not proof of which account an add-on call uses. Do not rely on editing /u/0/ or /u/1/ in the link to resolve this. Try the single-account route above.

If the file itself says You need access, first check which account it is shared with. Ask the owner for access for that specific email if needed; an add-on installation does not grant access to someone else’s file. Google’s file-access help explains the checks. For editing jobs, you also need permission to edit the destination.

If the problem remains in a single-account session, it may have another cause. Work or school administrators can restrict add-ons and connected services. Send support the add-on name, exact error and whether the single-account test worked; omit private file contents and passwords.

This guide applies to GeoFill, ColorSum, EventFill and PhotoFill.