How do I download my emails from Thunderbird with my 500GB passport plugged in.

Everytime I check my mail I have to unplug the drive completely. As you can imagine this is not ideal.

With it connected I click on ‘get mail’  and within seconds I get a box with the email details and a message about either a virus or disk space. See graphic.

This happens with every single email I get, spam or legit, but as soon as I disconnect the drive I can download them all.

I thought it was just my old pc playing up but I’m now using a new pc and I still have the problem.

I haven’t tried it with any other email program because I’ve been using Thunderbird for quite a while now and don’t really want to change. But if I have to, then?