Overview: Users may sometimes find that when opening certain binders in Excel, a Microsoft login popup/screen appears asking them to authenticate — even if they are already logged into Excel (profile picture visible at the top right).
If users attempt to log in via this popup, they may encounter an error stating that they do not have access to the relevant external SharePoint tenant or path, similar to below:
Cause
This issue occurs because Excel is attempting to access an embedded hyperlink or path in the workbook, which prompts the authentication request.
More Specifically:
Excel is trying to refresh or check the user's access to the embedded hyperlink/path.
As seen in the screenshot above, the popup often references a SharePoint tenant or path that is external, not our 'Active Collaboration' SharePoint tenant. This indicates that the workbook contains an external embedded link.
Resolution
1. Close the sign-in popup
When the authentication prompt appears, close it instead of signing in.
This allows the active workpapers taskpane to load successfully without interruption.
2. Open name manager in Excel
Thereafter, go to Formulas > Name Manager.
This displays all named ranges in the workbook, including:
Name
Value / Refers To
Scope
3. Look for the external/SharePoint path
In the Refers To column, look for any text that resembles a SharePoint path from the error message, e.g.:
https://companyname.sharepoint.com/...\\companyname.sharepoint.com\sites\...
To search faster:
Click inside the Refers To column.
Press Ctrl+F.
Search for keywords such as
sharepointor the specific site name.
4. Identify where the named range is used
There areseveral ways to locate the exact cells a named range refers to:
A. Edit the named range
In Name Manager, select the named range and click Edit.
The Refers To box shows the exact cells or range, e.g.:
='Sheet1'!$A$1:$A$10→ refers to cells A1 to A10 on Sheet1.
When editing the Named Range, Excel also highlights the range in the excel workbook. Click the Collapse Dialog arrow in the Refers To box to see the highlighted cells more clearly.
B. Use the name box (quick method)
Click the Name Box (dropdown to the left of the formula bar at the top of your Excel).
Manually type in the named range name and press Enter.
Excel will immediately select the associated cell(s).
C. Search across formulas
Press Ctrl+F.
Enter the named range name.
Click Options → Within: Workbook → Find All.
Excel will list all cells referencing this named range.
Click each result to navigate to the cell.
5. Identify and delete the problematic named range
For each named range pointing to the SharePoint path, note where it is used.
If the range is not required, delete it to prevent Excel from attempting to access that location.
If the Delete option is disabled/greyed out, go to File > Info and unlock all sheets, then try again.
Save the workbook, close Excel, and reopen it to test whether the popup issue is resolved.
6. Check workbook formulas and links
Review formulas, data connections (Data>Queries and Connections), and other links that may reference the same SharePoint path in Excel.
Update or remove any references that are no longer valid or accessible.
7. Update master templates (if applicable)
If the problematic named range or path also exists in a Master firm record template, remove it by going to Admin Centre > Record Templates. Download a copy of the template, delete the named range, and then re-upload the updated template.
This ensures that new binders created from the master template do not inherit the invalid external path.
8. Optional: clear Excel cache for persistent issues
If the popup persists due to other reasons, here are some places you can check:
Go to File > Options > Trust Center > Trust Center Settings > Trusted Locations and check for outdated paths.
Consider clearing cached credentials via Windows Credential Manager with the help of your IT.