One of the main advantages when we "unlock" our phone is that it will work with any SIM card, from any carrier (telecommunication service provider) in any country, but the process of unlocking can take up quite a lot from our precious time.
Telecommunication service providers often lock the phones which they sell or include in certain services because of their desire to increase customer loyalty by hampering their free movement from one network to another, blocking those phones into their own network.
Your phone is locked if you insert a SIM card from another network provider and it asks for a network unlock code (not to be confused with PIN numer).
Orange Stockholm as it name shows (a device from the network provider called Orange) is a locked or blocked device. It's a fact. But on the other hand if you own a Huawei U8180, it is probably not locked.
So the question becomes available: How do you unlock your Orange Stockholm?
Well, you can't unlock your phone by installing CyanogenMod or any custom or stock ROM, nor by any known software, nor by rooting the phone (in that case you can only uninstall branded software). I tried it, so you don't have to.
It can not be unlocked by those so called free unlock code generators, which generate a code depending on the IMEI code of your device. I tried a dozen of them only ending up with a blocked phone, not willing to show the panel in which to enter the unlock code because of the large amount of incorrect unlock codes I entered into my phones.
In the end your asking: Is it actually possible to unlock it?
The answer is: Yes! The problem is that it is not free. There are many offers on the Internet where you only have to type your IMEI code, I'm not going to advertise them because they differ for every country/region, and after paying the fee which is about 10 euro or about 10 pound they give you the unlock code by SMS or e-mail, depending on the type of the service. Or you can also check out your friendly neighbourhood mobile phone kiosk, or GSM Shop for the same amount of money. You can get your phone's IMEI by calling *#06# with your mobile phone.
Remember: Don't waste your time with free unlock code generators, because at the moment none of them work. Paying 10 euro for the unlocking of your Orange Stockholm isn't much, and this way you won't end up with a blocked device which would cost more to unlock.