Hi, I had a personalised theme which worked very well under Mendix 2.5. After upgrading to Mendix 3.1.1, the theme no longer worked but I was able to use the default theme. This morning I tried following the instructions to upgrade my theme for Mendix 3, but since then as soon as my application opens the screen goes blank. I have tried resorting to the default theme, but it keeps using my new (broken) theme. I have tried uninstalling all editions of Mendix and re-installing, as well as deleting all traces of the new theme I can find, to no avail. I also tried installing the 'themeworkshopv1.2' and still no joy: whatever I do I am stuck with the custom scheme which gives me a blank screen. Even if I make a new project I have the same problem. How can I get rid of my custom theme? Any suggestions gratefully accepted. Cheers Michael