I've been running BOINC for years on my PowerMac G5, OS 10.4.11
One day I had a problem & the graphics quit working.
I've uninstalled & reinstalled, but it didn't help.
The last time I re-installed it even wiped out my account & I had to sign up all over again.
Sure would like to be able to get the graphics running again.
Would really appreciate some help.
Thanks.

Which project is this on?
Do they (still) have graphics for the Mac?
Which BOINC version is this with?
Did you (ever) get newer drivers for your videocard/videochip?

The last time I re-installed it even wiped out my account & I had to sign up all over again.

No matter how much you uninstall & reinstall BOINC on your local system, that won't wipe out any account on any project server. You can only wipe out accounts there if you actually have access to the database on the server, which us mere mortals do not have on the projects.

A project can lose your account, if they have a catastrophic failure of the hardware (drives) and do not have any backup of their database. But then everyone will have lost their accounts and you will have noticed that on their forums.

So what's the most probable cause here is that you forgot which email address you signed up with and on the next BOINC installation signed up again with another email address. You can sign up only once with an email address, it's your unique identifier. Once it's in the database, you cannot use it again to sign up with. Unless you made a typo, of course. E.g. tried@tomas.ext is different from tired@tomas.ext or tried@thomas.ext (none of these are real addresses, spambots. :-)).

On any of the projects, when you get to the log-in screen you have links about "Forgot password?" and "Forgot email address?". Click those next time, then you can claim your old account back. But you will then have to choose which one to continue with. BOINC accounts cannot be merged.

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