Older computers (e.g. with 32-bit CPUs) may require older versions of BOINC. These versions should still work; however, they may be unable to communicate with some projects (and with the BOINC server) because the "certificate authority (CA) bundle" is out of date. (This file is a list of servers used to authenticate the certificates used for HTTPS communication).
To fix this problem, get a new CA bundle from here, put it in your BOINC data directory, and restart BOINC.
On Windows, the BOINC data directory is normally
This is a typically a protected directory and you won't be able to
download the file directly into it.
Instead, download it somewhere else,
then copy it to the data directory.
You'll get a dialog saying
You'll need to provide administrator permission to copy to this folder.Click Continue or provide the main administrator's password.
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