Compilation Error (Website Not Recognizing .NET 4.5) -

Compilation Error (Website Not Recognizing .NET 4.5) -

i trying website recognize new version of .net (4.5) can upgrade final version of dnn (7.2). have .net 4.5 installed when go iis settings, switch framework 4.5 (it says 4.0 bc version technically 4.03), , refresh local host error:

"compilation error

description: error occurred during compilation of resource required service request. please review next specific error details , modify source code appropriately.

compiler error message: cs1703: assembly same identity 'system.web.extensions, version=4.0.0.0, culture=neutral, publickeytoken=31bf3856ad364e35' has been imported. seek removing 1 of duplicate references.

[no relevant source lines]"

haven't found useful far on web regarding this. please help!

update: version referenced in web.config 3.5.0.0 issue?

your website needs configured utilize .net 4.0 .net 4.5 extension of version 4.0. depending on method utilize switch .net 2.0 .net 4.0, have replace references version 3.5 references version 4.0 in web.config.

compilation .net-4.5 dotnetnuke