We have not been able to open a Revit architecture model created in 2012 in 2013. Several of us have tried. It is a large model of a hospital. Any ideas?
Try to Audit before open it. Click Open, at the very bottom of the open window there is a check mark called "Audit", check that and click "Yes" to the warning window. This could take a long time to prosses. If you could open it, save the model as different name. Once you save it in Revit 2013, you wont be able to open with 2012.
Good lock...
I would suggest to audit, purge and completely clean up your model, i was trying to upgrade a project but i ended up having a corrupt grid line that i had to delete and that was preventing the entire project from being upgraded. Also there is an upgrader app that was developed see below link.