My code can not migrate from VS2005 to VS2010

Hello everyone, I have big a problem :S Normally I am developing application on VS2005 xp os but My code want migrate from vs2005 to vs2010, also My code is including seperate coded visual C++ and C# files, its running in vs2005 well, no problem but when my code migrated from vs2005 to vs2010 win7 os, I am getting thousands error

some errors:
"Error C4430:missing type specifier int-assumed Note: C++ does not support default-int"
"error C2143: syntax error: missing ';' before '{' "
"error C2143: syntax error: missing ';' before '^' "
"error C2065: 'e' : undeclared identifier."

what do I for it :( anything idea? advance in thankx... very nice for your answers :)

Post your code along with the errors, please