Users of Microsoft Windows Vista and Office 2007 might have encountered an error "Unknown error trying to lock file" when they click Edit Document. This error however didn't occur for users of Microsoft XP with Office 2007. As far as I know the problem occurred because of the changes made in the Web Client service in Vista and the way Office was communicating with Sharepoint. Installing Microsoft hotfix 943280 and patching your Web Folders with 907306 didn't resolve the problem. Trying numerous workarounds described on the web didn't resolve the problem either. The only workaround that worked setting the office applications to run in "Windows XP SP2 compatibility mode", but then why would you run Windows Vista. You could say this is another reason to go back old Windows XP.
Luckily with the release of SP1 for Vista this problem disappears! So, thank you Microsoft for solving this problem, although I hope such problems will be resolved faster and more efficiently. I would wish that those problems will not exist in the first place, but then I start thinking that if all software would run smoothly, it will make a life of IT guys pretty boring. So, thank you Microsoft for keeping IT guys busy/employed! J
Note: Don't forget to upgrade your SharePoint servers to SP1.
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