Don't worry. I made the same error.
There is a way to get out of this.
If you do not have already a second e-mail address, create one. Once this is done, change the e-mail address of the account you created with Boinc. You will receive a confirmation message. Please do not reply to this one.
Then create a new account by activating the account you had with S@H Classic using your original e-mail address. Here again, a confirmation message will be send to you. Reply to this one and start from zero. Attach to the project. It will very probably create another computer ID.
As you have now under the same name 2 different computers, you can merge these one by using the "View" in "Your Account" page.

Greetings from Belgium.

Hi,

this didn't work.
I got the "change-email-adress"-Mail, ignored this.
After this I activated my account and got the "new-user-mail", I used this acount-id for activation.
SETI@home member since 30 Jun 2004 15:13:14 UTC

Something seems to have changed, because the computer-information is gone.

Perhaps this date is resettet?
Is there any way to check if this is MY old account or a new one?


*edit*
well, something HAS changed, look on the dates, they are different, but still not correct.
*edit2*
and my userid here in the board has changed too. Seems I'm too stupid :/