As I’ve mentioned before, I’ve written a brand that is a combination of Theme and Master Page, and is designed to be activated by a feature receiver. When the feature is deactivated, it should restore the previous Master Page and Theme – but it wasn’t doing this for the default theme. Weird.
Well, here’s another good tip from Madalina you have to apply a theme of none, not Default.
web.ApplyTheme("none");
That’s the second tip of hers I’ve found on Google and used in the last 2 weeks. Maybe I should start watching that blog. Anyway, I guess that ‘none’ makes sense when you look in 12/TEMPLATES/LAYOUTS/1033/SPTHEMES.xml – the default theme has a TemplateID of ‘none’.
‘Course my next problem for my feature receiver is that Meeting Workspaces use master pages (MWSDefault.master) that are significantly different to other pages – thanks guys, that’s helpful…
Andy Burns' Blog 
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