i dont know from what version you are upgrading to version 7.0
there are documents to guide you trough the upgrade, you cant simply upgrade from version 2.0 to the current version. you need to upgrade the project to lower versions first.
If you look in the knowledge base there is a description in which steps you must upgrade your project.
Also when creating a backup don't forget your citect.ini file.
regards,
Marsupilami