Check Event Log:
Check your Event Viewer for these errors...
MSDTC errors (4427,4691,4135 are common error events for this)
W3SVC Event 36 "The server failed to load application '/LM/W3SVC/1/ROOT/'. The error was 'Class not registered"
Open "Control Panel" and then "Administrative Tools" then Open "Services"...
Locate the "Distributed Transaction Coordinator" make sure the process is "Started" and "Automatic"
(If its not, open a command line and type "msdtc -install", then try and start the service)
Open a command line and type the following...
rundll32 wamreg.dll, CreateIISPackage
(NOTE: "CreateIISPackage" must be typed exactly; it is case-sensitive.)
(wait for a dialog box to notify you asptxn has registered correctly)
Then, in the cmd prompt window type IISRESET
Open "Control Panel" then "Component Services"...
You should see all three IIS COM+ applications that have been recreated
Finally, open "Control Panel" and then "Administrative Tools" then Open "Services" and just make sure that
World Wide Web Publishing
are all running.....
As a very final check just stop and restart the web service in IIS itself.
With a bit of luck the COM+ and ASP/ASP.NET issue should be resolved.