[JanSH]

I came here to post the exact same problem. I have only just updated to 3.31. I did notice the installation for the first time insisted on a reboot, which I did. Attempting to download metadata now fails instantly with the "Failed to download metadata" and the traceback posted below (exactly the same as the others').

Windows 10 64-bit.

What I have tried (which does not work):
- Reboot.
- Repair install set
- Uninstall Calibre and reinstall to a different path on disk.
- Tear out my hair.

Any help would be much appreciated!

Traceback (most recent call last):
File "site-packages\calibre\utils\ipc\simple_worker.py", line 289, in main
File "site-packages\calibre\ebooks\metadata\sources\worker.py ", line 102, in single_identify
File "site-packages\calibre\ebooks\metadata\sources\update.py ", line 79, in patch_plugins
File "site-packages\calibre\ebooks\metadata\sources\update.py ", line 62, in patch_search_engines
File "<string>", line 11, in <module>
ImportError: No module named polyglot.builtins