CMS 7.1 upgrade issues
Since the release of 7.1 we have had a few cases reporting problems with the update and one example is that edit/admin mode ends up being white without any errors. One possible solution for this is to empty the Temporary ASP.NET files for the site and its listed in the Known issues section for the installations
We have received cases where this wasn't a solution and are investigating the causes for the issues. It has however been hard to reproduce but it got top priority within EPiServer and we will update the Known issues whenever we have more information.
If the section doesn't help for your installation then please report your problem on the link below and if you got an environment where the issue can be reproduced it’s even better: