I have moved DNN instance several times with no issues at all.

I am now trying to move a DNN5.6.2 on a new server and I am getting this error.

Line 179: -->Line 180: <!-- allow large file uploads -->Line 181: <httpRuntime useFullyQualifiedRedirectUrl="true" maxRequestLength="8192" requestLengthDiskThreshold="8192" requestValidationMode="2.0" />Line 182: <httpCookies httpOnlyCookies="true" requireSSL="false" domain="" />Line 183: <!-- GLOBALIZATION

Both servers are running windows 2003 R2The only difference from one server to the other is the DNN instance is presently running on a 32 bit version and IIS is set for .net 4.0

The new server is also 2003 R2 64 bit iis is set to .net 3.5

If I set the website instance to 4.0 the websites working under 3.5 now return

"The page cannot be found"

This is only happening with DNN5.6.X versions

All website instances are set to run .net 4.0

Any help will be greatly appreciated. I am the same issue on windows 2008 R2

No the new server is running 3.5 the old server is running 4.0 I am trying to move a site from the old server to the new, the new IIS instance is also set to 3.5 like the rest of the other iss instances

we have resolved the problem, we created 2 app pools one for .net 4.0 and one for .net 3.5 

I am new at this a basically felt  that downward compatibility meant downward compatibility

Thanks for your help