It is a dlopen() error, but what file is it trying to open? That is the $1M question.

Here are the permissions of my /boinc/projects/climateprediction.net/
...

Permissions look OK, maybe we should try to figure out if it starts from a certain BOINC version and does not happen with anything below.

(My CC 5.2.18 has not done anything weird on any CPDN box so far)

It's been surmised that the reason for the problem is that the BOINC API has left the program in the slot directory instead of its usual working directory.
This apparently only happens occasionally, and possibly only with hadam3p models, where library calls were changed.

It's probably not something that crunchers can fix.

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Backups: Here