I am posting this here because I get this error for multiple projects. It began after upgrading from ver. 6.x to 7.0.28, running on a Win Server 2008R2 machine.

Any thoughts?

Sounds like a permissions problem.
What's actually in the master_*.xml files of the affected projects? Did you check? They're in your data directory.

How are you running BOINC?
As a service, or not?
When do you get these errors, running it as administrator or as another user?
Are all those users allowed to control BOINC?
Are all those users allowed to write to the BOINC Data directory?

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Sounds like a permissions problem.
What's actually in the master_*.xml files of the affected projects? Did you check? They're in your data directory.

From master_cbl-boinc-server2.cs.technion.ac.il_superlinkattechnion.xml :
Unable to connect to database - please try again later Error: 2013Lost connection to MySQL server during query
This is the complete contents of the file.

How are you running BOINC? As a service, or not?

As a service, with protected execution

When do you get these errors, running it as administrator or as another user?

administrator

Are all those users allowed to control BOINC?

Yes

Are all those users allowed to write to the BOINC Data directory?

Only boinc_admins and Administrators can write to the directory

From master_cbl-boinc-server2.cs.technion.ac.il_superlinkattechnion.xml :
Unable to connect to database - please try again later Error: 2013Lost connection to MySQL server during query

I went to BOINCStats and clicked its link in the project list, this goes to the same error message. So sounds like the project is AWOL.

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