TheScruffyBear

Managed to fix the problem. Go into True NAS interface from Settings in Hex. Go to 'Apps' menu, click 'Configuration' drop down button, click 'Choose Pool', select your storage pool then click 'Choose' - the app service will then start, go back to HexOS and install Immich again and all will work.

I'm having the same problem too. Fresh install today of Hex and Immich just keeps showing 'Install' button. I now have a 'Photos' folder but the app doesnt want to install.