Your comments

thanx a lot. I am testing it now.
I meant ubooquity.conf instead of ubooquity.jar....typo.

Here I only made changes to the user dir:

exec /var/packages/JavaManager/target/Java/bin/java -Duser.dir='/volume1/prive/Ubooquity' -jar -Xmx1024m /var/packages/Ubooquity/Ubooquity.jar -port 2202 -webadmin



Parameter stoped working after restart Ubooquity. Do you know how to make your Java parameter permanent?
All non US-ASCII characters I can think of are recognized. I have added your Java parameter to the ubooquity.jar file and made the change permanent.

I think you can best edit the Matthew Sanders tutorial. Last part of the tutorial is about editing the ubooquity.jar file anyway
Done. Running a scan of my comics now. This is better then expected. I see comics with an umlaut in the name. No strange character or question mark. Will report on other non US-ASCII characters when scan is done.

Great job. Thanx a lot.
If you need someone to test on a Synology, don't be shy.

I agree. A question mark in the file name is much better then no file at all. Would your solution work on all non US-ASCII characters? Like: é or ô
The tutorial looks easy. But if I understand correctly, I have to do this every DSM (Synology firmware) update. Sooner or later I will forget. Don't know if I have to copy the comics to another machine every DSM update. But it sounds like to much hassle for just 11 comics containing an umlaut mark.

Best would be if Synology supports non US-ASCII characters. I will make a request to Synology for that.

I will remove the umlaut mark for those 11 comics. Looks like the most hassle free solution till Synology supports non US-ASCII characters.

Thanx for looking in to this.
I am running a Synology NAS.

Running DSM 5.2
I did report the same problem in this topic 4 months ago. I did a rebuild of all my comic files using ComicRack. Ubooquity is faster if you use cbz (zip) instead of cbr (rar) files. So I don't have the original cbr file's that would not open in Ubooquity. But my gut feeling say's Ubooquity has a problem with some older thumbs.db file's. When I put a new thumbs.db file to a cbr of cbz file Ubooquity seems to have no problem.