I have this error message
could not load assembly 'system.data.entity, version 4.2.0.0, culture=neutral,publickeytoken=b77a5c561934e089' or one of it's dependencies. the system cannot find the file specified
and I cannot use the entity framework at all. it happened after uninstalling June 2011 CTP from my computer, and I have no idea what to do. I reinstalled the visual studio again and with no help. Does anyone have any idea?
after reinstalling visual studio i found another insatnce of the CTP as part of sql server in the add/remove programs, after removing that all was well.
I had the exact same issue. After much frustration, I eventually resorted to re-installing the June 2011 CTP. Not ideal, but at least I can get on with my work...
来源：https://stackoverflow.com/questions/9565650/could-not-load-assembly-system-data-entity-version-4-2-0-0