I have Exchange 2013 installed on a 2008R2 server. All seemed to be working well including OWA, Activesync and EAC until I installed TrendMicro's Scanmail antivirus software. It seems to have broken IIS.
When I try to use any of these services I get a page that says "Server Error in '/owa' Application. The more useful message I get is in the application log. I am seeing event ID 1310 each time a user or device tries to access the server. I'll attach the entire message below but the essence of the message is "This assembly is built by a runtime newer than the currently loaded runtime and cannot be loaded. " I'm thinking the TrendMicro install used older software than Exchange but I don't know how to change it back.
Thanks for any help.