"can't set file "...<file path>\.svn\entries" read-write: access is denied.

I am getting repeatedly (cca. daily)
        "can't set file "...<file path>\.svn\entries" read-write: access is denied. Finished!"
errors. It's suggesting "do a cleanup", but then the cleanup itself fails (could not be performed successfully)...

The location of the directory on which I get these errors varies with (1) the places from where I make checkins and (2) the places where get updated by others.

Could this be related to the collabnet version I am using? To running it under tortoise on a Windows2008 operating system?
Any ideas/advice would be highly appreciated...

Thanks,
Pompi Diplan

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