If you try to swap users on a laptop, with Dynamics CRM installed in Offline Access mode, it will give the error above; searching gave me this page from the Chinese Dynamics CRM team, so I’m just going to repeat it here:

Basically, you connect to the SQL Server on the local computer, and delete the Offline Access database, allowing you to reconfigure as normal. Note that this won’t let you reconfigure the user as “online only” – the new configuration will automatically be Offline Access.

Secondly, this works even if the user is not Local Administrator on the computer.

I got this error message on a server while installing Dynamics. At first I thought the problem was that my IIS is running 64 bit .NET 2.0 (I’ve had problems with that in the past), but it turns out that the actual problem is that .NET 4.0 was installed.

This guy figured out what the problem is: The installer checks for a specific filter in the IIS settings, which doesn’t exist when .NET 4.0 has been installed.

I’ll repeat the fix here, hopefully making this a bit more “discoverable” by search engines (searching the exact error message gave me nothing helpful, just tips about running aspnet_regiis.exe -i repeatedly):

In IIS Manager, right click Web Sites, and select Properties.

Under ISAPI Filters, Add a new filter you call ASP.NET_2.0.50727, pointing to C:\WINDOWS\Microsoft.NET\Framework64\v2.0.50727\aspnet_filter.dll (assuming 64 bit server, otherwise substitute Framework for Framework64).

Dynamics should now install without issue.