Please attach the screenshot of the error dialog.

Does deleting this folder help? C:\Users\username\Graphisoft\IPC Data After uninstall is the C:\Users\username\Graphisoft\IPC Data folder empty?

http://helpcenter.graphisoft.com/troubleshooting/setup/cross-platform-issues/#Custom_folder_icon_issue AC18 and AC17 build 6004 no longer allow non-cross-platform files/folders in BIM Server Libraries. Custom folder icons on Mac create a file which is invalid on Windows.

Sections/Elevations/Interior Elevations store their contents in the plan file even if they are autorebuild type. So the more lines/shapes/etc. they contain, the bigger the plan file. Layouts also store the contents of the drawings, and also for every drawing they store infor...

What happens if you delete the files containing known servers/users? Win c:\Users\username\AppData\Roaming\Graphisoft\TeamworkInfo.xml c:\Users\username\AppData\Roaming\Graphisoft\TeamworkInfo_v2.xml Mac /Users/username/Library/Preferences/Graphisoft/TeamworkInfo.xml /Users/...