Since May 30, some older(?) BOINC installations are no longer able to access several projects with HTTPS URLs — e.g. LHC@home, NumberFields@home, Rosetta@home. The reason is the expiry of the "AddTrust External CA Root" certificate.
Some hints how to fix this are given in post 98900 by walli in thread "Peer certificate cannot be authenticated with given CA certificates" at the BOINC forum. The precise steps to implement the fix differ between operating systems. The BOINC forum thread generally does not have recipes which you could apply right away. You need to find where on your system the "AddTrust External CA Root" certificate is stored, and probably delete it. (Or perhaps replace it with one of the two newer root certificates; but just deleting the expired certificate should be the right thing to do in many cases.)
Edit,
several reports of what people tried in vain, and a few reports of what people tried successfully can be found in the thread "Peer certificate cannot be authenticated with given CA certificates" of the Rosetta@home message board.
Edit 2,
"reports what people tried" -> "reports of what people tried" — better? :-)
Some hints how to fix this are given in post 98900 by walli in thread "Peer certificate cannot be authenticated with given CA certificates" at the BOINC forum. The precise steps to implement the fix differ between operating systems. The BOINC forum thread generally does not have recipes which you could apply right away. You need to find where on your system the "AddTrust External CA Root" certificate is stored, and probably delete it. (Or perhaps replace it with one of the two newer root certificates; but just deleting the expired certificate should be the right thing to do in many cases.)
Edit,
several reports of what people tried in vain, and a few reports of what people tried successfully can be found in the thread "Peer certificate cannot be authenticated with given CA certificates" of the Rosetta@home message board.
Edit 2,
"reports what people tried" -> "reports of what people tried" — better? :-)
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