We have updated AppBuilder on Wednesday and it seems your issues might be related to the update not completing properly.
Please, follow this steps to attempt to resolve the issue.
1. Close the Windows client.
2. Run the Task Manager and kill any Icenium.Graphite.exe processes.
3. Uninstall the Windows client.
4. Go to %localappdata%\Telerik and delete the BlackDragon folder and the Icenium.Simulator* folder.
5. Go to %localappdata%\Apps and delete the 2.0 folder.
6. Download the AppBuilder bootstrapper from here and install the Windows client.
Don't hesitate to let us know if this does not resolve your issue. Thank you!
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