Well, 1033 means English, 1031 German.
So, avast! is trying to load the English resource modules... did you install the German version only?
many thanks Igor,
that's the hint I needed!
However, there's still sth odd in the installation, here the steps I've done:
1. you're right, I've installed in german, as admin the german language avast starts fine, as non-admin it fails as described.
2. adding english in the avast setting (as admin) succeeded, as non-admin the english avast starts. Both 1031 and 1033 directories are present.
3. As non-admin I cannot switch language back to german, the drop-down-box is empty.
4. Now avast fails to start when logging in as admin, message: Failed to load language dll [0\UILangRes.dll]
5. remove and re-installing avast in english: ok
6. add german as admin: Language setup error 0x2000000A. 2nd try is ok then.
Now same behavior as in 3. and 4.
7. remove and re-install in english only, register, then same behavior as in 3. and 4.
now all non-admin users seem to be ok, admin fails....
best regards
Charly