Can't sign in to Google Toolbar in my Firefox Portable

I had Google Toolbar installed and running perfectly in Firefox portable before I lot my usb flash drive a couple months ago.
I just got a new one and have installed Firefox portable and Google Toolbar successfully but the problem is that I can't sign in to the Google Toolbar. When I try signing in, the sign in page pops up, I am able to fill in the details, it loads but doesn't sign me in.
I followed the suggestions in the Google Toolbar Help: clear history, cache etc but to no avail. Even tried uninstalling & re-installing the Google Toolbar.