Why I have - 2500 credits on day 25 december ?
What is a negative credit ? Is is a bug ?

The most common reason is due to a split CPID.

Did a quick search of your user name and there are two Bosiota users in BoincStats. Check your RieselSieve account.

Good luck and Happy Holiday's.

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Thank you.
I see two 'Bosiota'. The second has only Riesel Project.
How can resolve the problem? I try to delete it without result....

Bye
Bosiota - Italy

I got the same problem. SETI was always on the same CPID, now since I added yesterday a new computer, it has a new CPID, messes my other projects up and I got now for 4 projects 2 different CPIDs, though having the same e-mail adresses and so on. This is just ridiculous, I lost 4000 credits yesterday. Updating my projects doesn't help so I guess I will stop crunching entirely. There's nothing more disappointing than a negative reward for having your pcs run 24/7...

So, either it'll fix by itself today or I'm out of every project. Guess my cpu cooler will be thankful :-/

You didn't lose any credits, they just happen to be on different IDs. The easiest way to make sure your IDs line up is to make sure you have one project that is common to all of your hosts. This may take a few days to happen and another day or so to get over to BOINCStats.

I don't know why, but my old CPID has returned back in Spinhenge project. Unfortunately the SETI CPID is still wrong. Well, guess I have to wait until I'm back at home :-/

SETI has still the wrong CPID. I don't know that to do. I tried it on 3 hosts with updating and so on but it still keeps the wrong CPID.

OK, now every project synced... with the wrong CPID. Wow, never seen such random programming like this -.-

That's what happens with random number generators.

And it's not the wrong CPID, it is your new CPID.

It's not exactly random, when the boinc client has two projects with different ID's and the same email, the one with the oldest creation time is used. They might change this in the future so they'll use the one with the oldest ID.