Yeah, still doing it. Can anybody advise?

Do the documents in which you created the style still have it? Please advise.

I've got the tab to stay, and double space. But I have to remove "add space before/after paragraph" manually each time. No, "updating style (manuscript) to match selection" doesn't save it.

I've tried rebooting the PC, to no avail.

Set the Spacing Before and After to zero by clicking Format and then Paragraph in the Modify Style dialog box. That way, the setting would stick.

Note that when selecting "New documents based on this template" fails, you can work around it by opening the template directly (as a document) and modifying the style in the template. To resolve the underlying issue which is preventing you from changing the template, troubleshoot for poorly designed add-ins, as Charles has already suggested.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional