I have the same problem. I created long ago a .mac account and I never used the payed MobileMe service.
I used that .mac account as my AppleID (usually I use a Gmail address), then I was asked to choose an iCloud e-mail. Tried to use my .mac username, no succes (already taken... by me!).
I thought that with iCloud all .mac and .me (created with MobileMe) were going to keep working... maybe it's a launch day hiccup.
Thanks for your help.
I had a mac.com/me.com trial and I cannot log into MobileMe to move it over to iCloud via http://me.com/move.
I went through the password recovery and e-mail option but no luck.
I also tried to send the address a message and received a permanent failure:
550 550 5.1.1 unknown or illegal alias: firstname.lastname@example.org (state 14).
How do we get access to these type of inactive MobileMe accounts?
Not sure if this is the same as "merging" the two accounts, which is what I believe Apple is working on,
According to Apple it's not possible to merge accounts > Frequently Asked Questions About Apple ID
What I found weird is that this isn't exactly merging accounts. I have a real Apple ID I use all the time and I have a broken "email@example.com" address that I got from using a Trial of MobileMe/.Mac awhile ago that Apple thinks is being in use. That address is not active. It gives an error when you e-mail it.
So, while they think I am asking to merge these two things, I am trying to figure out how to deactivate the "firstname.lastname@example.org" address or at least rename that Apple ID (if that would work) so I can use it for mail with my real Apple ID in iCloud. I suppose they define that as merging two Apple ID accounts, but the problem with the "email@example.com" account is that I don't have the password for this inactive account, the password recovery is sending the e-mail to an inactive e-mail account ("firstname.lastname@example.org") and the personal identifical information is wrong. I actually don't think it is wrong. I think it was never entered and it is impossible to recover.
There are probably more cases like this that could be solved if Apple was willing to purge the system of users that haven't paid or logged into the system in many, many years. I guess we are learning what the actual advantage of being a paid MobileMe user for all those years actually was!
Count me in with the same problem. I have my old MobileMe login info, but since its been deactivated I can't get in there to delete the addresses. I had a bunch of alias' I like to use, and now none of them are available. I probably would have paid to activate the account prior to the deactivation, just to get those email addresses, if I knew they would never be "released back into the wild".
However, you can use Lion 10.7.2 or iOS 5. Simply enter your disabled email@example.com with the correct password, and it'll be converted to iCloud automatically. After that you can also log in on icloud.com.
Edit: one more gotcha. To use Mail again, after you've enabled Mail in Lion or iOS for this iCloud account, go to the me.com website. Log in (that will work now) and it'll show you a link to iCloud.com. If you only log in to icloud.com, it'll keep telling you you need to create an email address.
from the macrumors forum.