I first signed on with SETI@home maybe 20 years ago, so long ago that I forget my original sign-up info: screen name, email, password. This has not been a problem, for as I've migrated from one iMac to the next my account settings were automatically transferred by Migration Assistant. This time is different. I want to connect my new iMac to my long-standing account balance but I don't know how. I created a new ID, but I still want to find out and use my existing one. Any suggestions?

Bork,
AKA Brian Noonan in New Haven, CT.

Those such as myself who have transitioned from Windows to Linux have had to deal with this problem as hosts changing Operating System types don't get the same Host ID. They get a completely new one because of the platform change. But if you want to keep the old Host ID, creation date and credit history, you have to do some editing of the client_state.xml file.

What you need to do is to edit the old hostid into the new client_state file of the newly created host. You also have to increase the rpc_seqno count by one. You can do that by looking at your Computers list on the website and look at the old host you want to reclaim. Look at the "number of times the client has contacted server" on the hosts Details page. Write down that number. Now increase that count by 1. While there make note of the Computer ID on the website for the old host.

Now open the client_state.xml file on your new machine and replace the <hostid>your new host computer ID</hostid> with <hostid>your old host computer ID</hostid>

Do this for ALL project sections that you are attached to in the client_state.xml file, substituting the old hostid for the new hostid that was created when your new machine contacted each project and picked up a new Computer ID.

Next find the <rpc_seqno>N</rpc_seqno> parameter for each project and put in the number of times the client has contacted the server number increased by one. Do that for each projects section and the number of times the old host had contacted the projects servers.

Save the client_state.xml file as an .xml file. Don't let your editor try to add a .txt suffix to the file. Now delete the client_state_prev.xml file which is a copy of the client_state.xml file. You don't want the next connection to auto correct the newly edited client_state file with old information and ruin your edits.

Doing these edit will allow you to keep your old Computer ID for each project with the original creation date and the credit history.

[Edit] You also may want to set NNT and finish all your work on the new host since any tasks on that new host will become "ghosts" after you revert to the old Computer ID.

It is not possible to change the HostID in that way unless the two hosts are attached to the same user account (email address). I think the enquirer said that the original email account and password had been forgotten.

If you still have the previous computer which had been attached using the migration tool, or even just the hard disk from that computer, all is not lost.

Finish off the current work on the new machine (set 'No New Tasks') - that won't be transferable either. Then, use BOINC Manager to 'Remove' the computer from the SETI@Home project - leave BOINC installed as it is.

Then, find the file

account_setiathome.berkeley.edu.xml

on the old hard disk - it will be at the top level of the 'BOINC data directory', but somebody else will have to help you find that on a Mac. Use a USB stick or suchlike to copy it to the equivalent place on the new machine, and you should have your old account back next time you start BOINC.

Thanks Richard, I see I had missed that important piece of information.

On a Mac:
Macintosh HD -> Library -> Application Support -> BOINC Data