Thank you very much.
Now it is working again.
I was installing and uninstalling 2 more times, because I got into another conflight with 2 other webassist extentions. I was loosing 4 working days and use a lot of hours to manage the problem. I will suggest, that all your extentions look for conflights, when people install them, so if there already are extentions installed, a message will give the users a opportunity to stop installing other extension, which will create conflights.
For us, who do not have your experience, and know how to solve the problems, it will be with a lot more pleasure to buy and install new extentions.
One more time, thank you for your help.