This may be one of those things where I am the real cause of this error is totally unrealted to how I perceive the problem, but right now it seems like the folder name ‘bin’ causes problems with webDAV folders.
With a virtual folder on an IIS server that uses webdav, if you create a folder called ‘bin’ you get the following error when trying to access the folder or modify.
'Documents in this folder are not available. The folder may have been moved or deleted, or network problems may be preventing a connection to the server. There is a problem with the webserver. Please try again later or contact the server administrator.'Many other folder names worked fine. May be related to the following issue: