[jmcinvale]

Worked fine ever since I got the phone then the phone screwed up and on that phone I could not write to the sd card after that.

I then installed the motherboard from one I got just for the display a year ago because the phone finally bit the dust and same problem.

Even the camera app which can save to the sd card won't write to it.

Does this mean I have to format the card or is there something else wrong or is there a setting I need to change?

I've even tried several file explorer apps and no dice.

[Rukbat]

One app can't write to a folder on the card that's owned by another app. Bear that in mind when you try to figure out the problem. The only "folder" that any app can writ to - and it can only create folders there - is the root of the SD card. (So have the camera app create its own folder and it should work after that.)