A customer cannot remove file/folder in their Windows webspace using File Manager in the POA Customer Control Panel due to the following error:
The path "very_long_path" goes out of the root directory.
The full path to the file/folder (including AD entries) to be removed exceeds the Windows API 'Maximum Path Length Limitation' 260 characters.
Read the following Microsoft article for more details about the Windows API limitation - http://msdn.microsoft.com/en-us/library/windows/desktop/aa365247%28v=vs.85%29.aspx#maxpath.
Remove the files/folders directly on the corresponding Windows server.