Terribly slow startup and cannot connect to mail account

Friends

I have a strange problem on two computers when using TB Portable (latest version, 3).

Here are the details:

Vista (one is 32 bit business and one 64 bit business)
Thumbdrive Kingston Datatraveler 1 G and 8 G (behavior same on both)
On a local network with a domain server and a 2 MB broadband subscription
Running inside a Truecrypt file container (2 G and 300 MB)
The computers are both fairly new and powerful.

I did a fresh installation of the latest Truecrypt and created a TC file on two thumb drives. One 2 G and one 300 MB. Then I mounted the TC file. Then I installed the latest portable TB onto both of those TrueCrypt "drives".

I noticed when I did that Portable TB installation that it was waaay too slow. It took more than 10 minutes to install the Portable TB onto each of those thumb drives (with USB 2 drives and ports)!! Ok, but it installed, in the end. Then I created an account in P TB and that worked just fine too, but slow.

Finally I shut down the Portable TB and restart it. It takes over TWO minutes to load the program, each time. Plus when I try to connect it does not really get anywhere. It says connecting but it seems that because of slowness in the system it does not even get to actually try to connect to the outside before it says either time-out or the settings for the SMTP server is incorrect, when sending! But that is not the case. I use the same exact settings on two other non-portable TB computers.

We tried it on an XP machine in the same office and it worked, and much faster. Took only about 25 seconds to start, and then it worked just fine.

I am not sure where the problem is. Is it Vista? Is it Truecrypt (I tried both TC 6.2 and 7.0)? Is it the domain? Is it the thumbdrive (it is formatted in FAT, and it is optimized for speed, i.e. caching)? Is it some kind of combination of two or more of these or what could it be?

Any suggestions would be welcome.

Thanks
Calle