Odd 404 Error with aspx pages

Ran into a situation that took me a little troubleshooting recently where .aspx pages would not show up in a browser, instead would only display a 404 error. Looking in the IIS log I found the following:

127.0.0.1 GET /Default.aspx - 80 - 127.0.0.1 404 2 1260

Long story short, this server didn’t have .Net4 registered. To fix, drop to a command line, and issue

aspnet_regiis.exe -i

from the appropriate .Net folder. (ie: windowsMicrosoft.NET4.0.30359Framework643.0.319)

That should be it!