I am currently running a Sitecore 6.6(rev. 121015) on Windows Server 2008 R2 web server and I am trying to migrate it to the web server running on Windows Server 2012 OS. When I did I am getting dependency errors for my project dlls. I found an article that says Sitecore 6.6 CMS is not compatible with Widnows Server 2012. Is it correct? If yes why is it not compatible? and Is there any workaround for it?
Thanks in advance.
You can find full compatibility matrices from Sitecore on their KB site:
https://kb.sitecore.net/articles/087164
These essentially outline what setups will be supported by Sitecore. If this is a system for which you wish to be able to receive help from Sitecore support, you should not install it in a configuration that is not supported.
If windows server 2012 is required, I would recommend upgrading to Sitecore 7.2. Moving from 6.6 to 7.2 is relatively simple, and 7.2 is much more stable and feature-rich than 7.0 or 7.1. It also lacks the additional changes that occurred to the infrastructure (Mongo) in 7.5 and 8, so makes for an easier transition.
I cannot be sure as to the 'why' it is not supported, but my guess is that the underlying .NET support in 2012 is not compatible. That would be just a guess, though.