Thank you! But I managed to solve the problem yesterday evening after posting the question. In addition to uninstalling the earlier version of Inkspace (that did not work) I had to log out and restart my computer. After that Inkspace could be reloaded normally.

Inkspace stopped working. This has happened once before. Then I re-loaded Inkspace and everything was OK. Now I tried the same, but when I try to re-load the program says that it cannot write in the file ...\inkscape.exe and stops re-loading. What should I do?