The source was not found, but some or all event logs could not be searched. Inaccessible logs: Security

We have upgraded from VS 2005 on windows server 2003 R2 to VS 2012 on windows server 2008R2
The asp.net applic code with statements eventlog.writeentry("src","msg") started failing with the error "The source was not found, but some or all event logs could not be searched. Inaccessible logs: Security"
So to resolve the error, as per online suggestions, I had to create the event source key at the location HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\eventlog\Application and create a string "EventMessageFile" with value: C:\Windows\Microsoft.NET\Framework\v2.0.50727\EventLogMessages.dll
I never had to do this on Windows server 2003R2. Can some one please provide me more insight into this?
Is there an alternate way to resolve the error without having to create the key in the registry?