@diskborste Thanks for checking the pages. I made a 2nd test from another pc with new SeoTools-Installation and it worked as well.
Now I reinstalled SeoTools on my main pc - but this time with deleting all AppData and now it works fine again. Seems like I had a misconfiguration in my SeoTools.config.xml.
@nielsbosma Maybe you could add the deletion of the AppData when using the "remove"-function in the Install Wizard?