DB version for mobile

What swl db version is required when using mobile client

You need to have the latest version of sambapos 5.2.3 it auto updates database when you install.

But there is a comment that a different vetsion of SQL express is needed

I doubt SQL version will have effect unless using something really old.
It would more likely be that SQL express is needed over LocalDB which is like an SQL lite for single terminal setup…
Pretty sure that Microsoft doesn’t offer download for older than 2016 now anyway.

What comment? Can you show us.

Mobile client access requires SQL Express FULL (multi-connection) rather than SQL Express LocalDB (single-connection).

The DB Engine version does not matter. I expect it would work with SQL 2008, 2008 R2, 2012, 2014, 2016, and 2017.

The SQL Express 2014 version you can install with SambaPOS 5 is the LocalDB version, and will NOT work.

From my experience you will need the 2016 as a minimum but since it is no longer available in Microsoft, you will then have to use the 2017.

The 2014 LocalDB version that comes along with SambaPOS installation and the full version 2014 will not work.

The full 2014 will work it’s localdb that won’t.

Then I am not sure why.
My R&D system used to run 2014 full version. It does let me install but several modules on the client side will crash until I upgrade to 2017

I run 2014 still on all the tills I manage… Just because Express is installed wouldn’t mean your using it, it all depends on the connection string.
Define modules? more likely a config error.