Thanks for your contribution. Experiencing the same problems with the same error message. Site was completely down. Solved with the solution offered. Didn't have the problem on any other site I manage. Thanks again!
If the Joomla updater errors out your best solution is to manually upgrade the plugin and/or template as posted here.
SEARCH the forum first! These boards are rich in knowledge and vast in topics. This includes searching just the 'Solved' forums, using Google, and using ChatGPT