While installing the Dynamics CRM Data Migration Manager on a Dynamics CRM server, you might get this error message:
The path is not of a legal form
To solve this error you should go to the registry and change the InstallLocation of the CRM server. The location is different for x86 and x64, but can easily be found by going to:
In this key you should search for the key which contains "Microsoft Dynamics CRM Server". This should bring you to a location like:
In this key you should set the value for "InstallLocation" to "C:\Program Files\Microsoft Dynamics CRM ". The installation of the Dynamics CRM Data Migration Manager will then continue.
Credits for this solution go out to the CRM community where I found this solution.