The software itself is stored on the USB stick.
Seems you have to delete all T-Mobile software on your Mac so that when you connect the stick, the Mac OS then will "only" recognize it as a "new simple" USB storage stick.
Only then will it display the "content" of the stick.
As in, the installation program for the T-Mobile software. On my stick it was an installation package (application) and an uninstaller.
This is difficult! 🙂
Seems that the contents varies between different types of sticks.
I can just repeat (and translate) what worked on ONE type of stick here in Germany. And I´m not sure it´ll work for you. As I said, different kind of sticks seem to include different kind of software packages. So don´t be mad at me if it doesn´t work.
1) Once you´re shown the contents of the stick, don´t use the automatic installer! We all know by now that this leads to problems.
2) Right click on the application package and choose "Show package contents".
3) Choose folder "Contents" and then folder "Resources"
4) In folder "Resources" you hopefully see only one package named something like "Mobile
Connectxxxxxxx.pkg"
(If you see more than one I really don´t know what to do. Try one? If it doesn´t work, delete everything and try the next?)
5) Double click that package. It will only install the drivers for your T-Mobile stick. Not the faulty software.
6) If it works, it should install the drivers for your T-Mobile USB stick.
And opening a window telling you that "New network interfaces have been detected".
7) You should then be able to got to "Network preferences" and manually configure the stick.
I downloaded the "web'n'walk Manager" from the Austrian T-Mobile site and checked it out. It does have an "mpkg" file but that file seems to include everything (drivers and the faulty T-Mobile software). And the "Resources" folder there included several "pkg" files....
Problem is, I don´t know the software stored on your stick.
Maybe your UK web'n'walk Manager just includes the drivers necessary for your stick?
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And by the way, websites here in Germany report that T-Mobile Germany acknowledges that problems using Snow Leopard and T-Mobile USB sticks seem to be a widespread problem. And if you complain you will get a rebate / won´t be forced to pay for days (if you have a flat rate) for the days you couldn´t connect to the Internet.