Can I transfer a Windows 7 license to another computer?

If you are purchasing a "retail copy" from a shop, you should not have any problems transferring it to another computer.

If you do run into a problem activating (which occasionally does happen) simply calling the Microsoft activation line (number given during the activation wizard) will allow you to activate it with a special code that you type in.

You can activate your license 2 or 3 times, so you should not have any issues. Worst case you will need to phone Microsoft to get the unlock key, but it is a fairly painless process, and I know in the States you can now even SMS them your code and they will send you back an unlock code.

If you are using a full retail license you will have no issues

Note however:

An OEM 'system builder' license must stay with the computer it is first installed on. (I believe it links with the motherboard).

For a upgrade license, my understanding is that, if it is installed over an existing OEM install, you can't transfer the 'full' license to another computer - only the 'upgrade' part. However this shouldn't be a problem if the 'underlying' OS was a full retail copy to begin with.

If you have a retail box of Windows 7, you can install it up to 3 times. After 3 times, your Windows 7 dvd turns into a frisbee.