The ASP.NET install path could not be determined from the registry - CRM 4.0 Client Error - Windows XP

Same error as my previous post, however you will need to re-register your microsoft framework to clear the error

i.e.  C:\Windows\Microsoft.NET\Framework\"Version that your crm client is using"\aspnet_regiis - i

To find out the version that your CRM client is using, go to the below registry location

\\HKLM\Software\Microsoft\MSCRMClient\AspNetPath\

Enjoy

Jonathan