Exporting tracks onto USB drive - lot of tracks not working.

Hello, I have my small initial collection from my stationary PC.

I bought an external SSD and gave it drive letter T: Filesystem is exFAT. I only want to play from my laptop.

1) I created a playlist and pasted all the 1038 tracks to it. Then I exported the playlist to my external T:

Turned on laptop, tried to play the tracks in RB, a lot of them are getting exclamation mark and do not play.\

2) I exported all the tracks straight to T: using the RB option available.

After starting from laptop even more, ~250 tracks are unplayable.

I just want to transfer all my collection to the external SSD and use it on both PC and laptop. Help appreciated.