QNAP [Apache85] Install Error "Failed to install Apache85 - the system volume is missing" although in QuTS Hero Storage Manager I can see a system volume?

[rbbrtl]

Hello,
I have purchased Apache85 (both for its functions and to support qoolbox in his amazing efforts), but fail to install it properly in my TVS-h874T. I tried both by download and by adding my personal repo to the App Center and installing from there.
I activated the QuTS Hero 6's internal Web Server first, no changes made there - just the default - I also then see the "Web" share, which also is accessible. In Storage Manager, I see an Entry of a single SSD as "Storage Pool 1 (System)" (and a RAID0, which for a single one is odd, but ok).
However, when I now try to install Apache85 (same btw for Q-Multimedia-Q6), it downloads and starts to install, but then fails with the error

Error 2026-08-26 11:28:56 <adminusr> 10.10.10.50 Web Desktop Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:154.0) Gecko/20100 App Center Installing/Updating/Removing Apps [App Center] Failed to install Apache & PHP 8.5.x. The system volume is missing.

(as I also mention Q-Multimedia (Q6), the error is similar:
Error 2026-08-26 11:36:34 <adminusr> 10.10.10.50 Web Desktop Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:154.0) Gecko/20100 App Center Installing/Updating/Removing Apps [App Center] Failed to install QMultimedia (Q6). The system volume is missing.

Not sure what my error is here - can anyone pls assist?
One thing might be worth mentioning - there used to be a RAID5 Storage Pool 2 in the system that had its issues and got deleted recently, but it was not marked as the system pool, so I am not sure if that can play a role or not.

Thanks for any help!

Martin

 

[rbbrtl]

PS: I also checked the thread https://www.forum-nas.fr/threads/rclone-the-system-volume-is-missing.26913/ which reports a similar error, and I also added the entry "defVolMP = /share/ZFS1_DATA" in /mnt/HDA_ROOT/.config/def_share.info (it was missing in that one, but it WAS available in /etc/config/def_share.info):

head /mnt/HDA_ROOT/.config/def_share.info
[SHARE_DEF]
defPublic = Public
defDownload = Download
defMultimedia = Multimedia
defRecordings = Recordings
defUsb = Usb
defWeb = Web
defVolMP = /share/ZFS1_DATA

I added this last line (it was not there before) after checking
head /etc/config/def_share.info
[SHARE_DEF]
defPublic = Public
defDownload = Download
defMultimedia = Multimedia
defRecordings = Recordings
defUsb = Usb
defWeb = Web
defVolMP = /share/ZFS1_DATA

There is lots of space on share "Public" as well, no quota, not limited.

I also rebooted the NAS after that change.

Thank you for any help!