Thunderbird 3 USB Hard Drive Connection Issue

Hi,

I've been using portable Thunderbird on an external hard drive for years now and about 2 weeks ago upgraded to version 3. Since doing that I encountered an issue with my portable hard drive (Freecom) that manifested itself as Windows disconnecting and reconnecting the hard drive (although not always reconnecting unless I did it manually). The tell-tale windows USB connect/disconnect sounds play when this happens.

This would happen many times a day, crashing Thunderbird and other portable apps I had open (Firefox, Filezilla etc.) It became such a problem that I came to the conclusion that the hard drive was on its way out, so I purchased a new one (Toshiba) and transferred everything to that a couple of days ago. Unfortunately the problem did not go away so yesterday I reverted back to using Thunderbird 2 and haven't encountered a problem since. The big problem is that this random disconnect/reconnect has caused data loss (although as I have backups that isn't so much of an issue).

I can only come to the conclusion from this that there is something wrong with Thunderbird 3 when run portably. Has anybody else experienced issues with Thunderbird 3 and portable drives? The version I currently have installed is 3.1.4 but, as I say, I've done back to using version 2 for now. I'm running Windows Vista Ultimate.

Thanks