Unlocking Tchibo surf stick

[Lucy]

I have a Tchibo surf stick I use in Germany. I would like to unlock it to use in other countries.

I have seen suggestions of and links to websites that promise the unlock codes, even apparently for free. (Unless the price comes up after you click on the link.)

But I am hesitant to get involved with sites I don't know, especially if they appear to be in Asia or Russia or Eastern Europe.

Has anyone used one of these sites without getting into trouble?

Would unlocking the stick in any way prevent me from using it in Germany on the Tchibo system? Would it allow me to use it on the O2 system?

[inquisitor]

Check out this thread: free unlock code calculator for Huawei modems on the web

And yes, it works, it's absolutely free and there's absolutely no security risk - you don't need to download anything, you don't need to share any personal data or provide a credit card - you just enter the IMEI (serial number) which you'll find on the back of your stick and after a click you'll get your unlock code.
In order to actually unlock your stick, insert a SIM card from any other operator and after starting Mobile Partner you will be required to enter your SIM's PIN code (unless disabled) and afterwards the unlock code et voilà.