I could not remember my password when I change to new BOINC program so I had to start from the beginning, now my credit is 4883 but should be 8882. I had total credit 3999 in my older version of SETI program.
How can I change this?

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You did not have any credit in Classic Seti, you had so many results returned.

Read in the BOINC-Wiki:
Credit
Claimed Credit
Granted Credit
Pending Credit
And Seti@Home and Credit

Now then, you cannot merge two accounts. The password that was meant for the old account (Classic), was an 8 to 10 digit (numerical) password that you could request at the Seti server when it was still available. You never set it yourself.

This form would then allow you to take the Classic account and start crunching BOINC/Seti from zero credits, while you had your Classic results visible as a memento to the past in your account.

So there's your answer. If your present email address is different from the one you used at Classic, then there is no way you can "merge" the two accounts as you wouldn't have the "password".

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