Thank you for reporting this.
It seems that the upgrade log creation failed for some reason. I've tried to reproduce the issue, but with no success. Is it possible to send us a project that reproduces the issue?
As a temporary workaround, you could try to disable the 'Show upgrade log when the Upgrade Wizard finishes the update' option. This should prevent the wizard from the crash.
Regarding the Expression_Dark problem, there are several possible scenarios:
- The reference to the theme assembly (Telerik.Windows.Themes.Expression_Dark.dll) has been removed (if the theme was referred from an assembly)
- The XAML resources has been removed (if the theme was referred from a XAML resource)
- The controls assemblies were updated from NoXaml version to a standard version
The first two scenarios might have been caused by the Upgrade Wizard crash, so please try the workaround above and check again if the problem persists. The third one is self explaining - the fix is to choose the correct distribution at the fist step of the upgrade wizard.
I hope this information is helpful. Let me know if I can be of further assistance.
the Telerik team