You say that you have tried "try activating my 3DS, before the computer finishes activating it", what happens if you just get a new code, fully let your computer complete the activation process, then head to your 3DS and start up the Netflix program.

3RDMARIOBRO  wrote:

 

Well basically, I had my 3DS on the Netflix channel so I knew the code.  While that was open, I typed it into Netflix.  While Netflix was activating on the computer, I still had my 3DS on the Netflix channel.  Is that not how it's supposed to be done?  Before the computer even finishes activating, my 3DS tells me the code expired.

Since I have already used my free one month subscription to activate Netflix on my Wii console and didn't continue with the paid subscription, I can't say for sure how it may work on the 3DS, but try writing down the code, exit the Netflix Channel on your 3DS and then see if that will work after activating it on your computer.

Just to be clear, the 30-day free trial is for Netflix as a whole, not for each device.