Access to the path '\\users.winlan.net\users$\' is denied

We get the error message in three situations:

(1) - save a Map report as PDF (report preview window)
(2) - open a linked document from within form
(3) - exporting form data as ascii/excel file 

error message when trying to open a linked document

All users have a private folder on the network. The folder is connected as a drive, the root folder is "\\users.winlan.net\users$\". Map now tries to save a file in the root folder - but a user does not have any permissions there.

The following "solutions" are available:

(1) - save a Map report as PDF (report preview window)
- the pdf file is - despite the error message - saved locally in "C:\Program Files\Autodesk\AutoCAD Map 3D 2013\Temp". A user can open the file from there.

(2) - open a linked document from within form
- save the drawing first on the network drive, two levels below the path given the error message (in my case that would be: \\users.winlan.net\users$\users\frro3 - basically my root folder on the drive).

(3) - exporting form data as ascii/excel file
- The problem does not occur on all machines. On some machines Map just crashes. The crash report contains the error message mentioned above. On some machines the crash can be avoided by accepting the default path in the "Save" dialog. On some machines export just works. By the way - the crash only happens when you save the data as shown in the form - no matter whether you try to create an excel or an ascii file.

crash on some machines when trying to export form data

Map 2013, SP2