Admiror Gallery cannot create thumbnails / permission 755

[06pichlw]

Hello!
Though I read all topics about this problem I can't find a solution.
Thumbnails are being created when I set folder permissions to 777 in the thumbs folder and everything works fine. But I can't get it to work with 755. Even when the thumbs are already created under 777 mode, switching back to 755 shows me this error log:

Admiror Gallery cannot create thumbnails in /www/htdocs/xxx
Check folder permmisions!
Admiror Gallery: 4.5.0
Server OS:Apache
Client OS:Windows NT 4.0
PHP:5.3.28-nmm1

Is there no possibility to create thumbs with folder permissions 755?
One thing: The ownership of the created thumbs are different (33 33) to the files I upload myself.

Has anyone a clue?
Thanks!

[Admiror Joomla! Sponsor]

[Vasiljevski]

You should be able to create thumbs with 755, as you know 777 is not safe to have

Script that creates the thumbnails has the same permissions as the user that executes it, in your case Joomla and at the end PHP.
So my guess is that you should check you server configuration.

But I can't be sure that it is not something else.