PC connection

Hi
My UMI eMAX phone has always connected to my Pc OK & given access to all files, mostly stored on SD card.
Yesterday it connected OK, folders showed up but were empty. Checked folders using phones explorer & they are still there. Put SD directly into PC & no problems.
This is what I have tried so far without success.
Different cables.
Updated driver on PC (it was already up to date).
Connected phone to a laptop, same problem.
USB setting is on MTP, changed it to charge & the put back to MTP.
Cleared apps cache.
Now here is the odd thing. I took some photos, connected to PC & the new pics showed up but the 1000+ old ones that are on the SD card did not.
Any thoughts please?

 

Thanks.
Will check those ideas out later. I am currently cooking.

 

Cooking update. Two chicken and mushroom pies for the freezer and smoked haddock with tomatoes & shallots tonight.
Phone update . Found another brain cell & recalled an error message when I last put the SD into the PC. Scanned and fixed whatever the problem was. Back in business..
You might be able to assist with this. I was thinking that this phone which is on Android 4.4.4 needed replacing, any suggestions? Similar to this but more up to date. ie. mid range phone.