My Sony Vaio was delivered with W7 Home Premium. At work we have a license we are allowed to use for the Enterprise version. Can I do the upgrade without the risk of loosing data on my PC? How shall I do as my first attempt failed, Enterprise required a clean disc.

As far as I know Enterprise requires a clean full installation. Enterprise has features that are not in the other versions so there is no way for the Anytime Upgrade to 'unlock' features. You can use the Windows Easy Transfer to export you settings and data but all the programs will have to be re-installed in Enterprise.Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.