Whilst you can store copies of dotx and dotm templates in Sharepoint, I don't ever expect the template to work with documents while they are there. I always have the templates loaded into my User Templates folder (and have IT run scripts to deliver updates to people's machines). Then the users can open any document and the template gets found automatically.

I believe (without real proof) that documents get confused when people edit documents in Browser mode rather than opening the desktop app. Unfortunately, Sharepoint makes it way too easy for authors to make quick edits via the browser.

That said, I have not had problems with table styles changing randomly. I would firstly check that you don't have multiple copies of templates sitting in various locations. When Word opens a document, it reads the name of the attached template and then goes looking for a template with the same name in at least FOUR different locations. Also verify that the "Automatically update styles" setting is not turned on.

Another area to check is the color palette - if the table styles were coloured using design palette colours then if those colours change the table will display that change.

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Andrew Lockton
Chrysalis Design, Melbourne Australia