Package manager message "Could not cache ..." what does it mean?

Hello, I getting these messages whenever I try to install/update addons with package manager on my test site. Not sure If I was seeing the same error before. Any pointer to root cause this error is appreciated. Below message is from Wayfinder install.

Error writing preserved objects to /mysiteurl/m/core/packages/wayfinder-2.3.1-pl/preserved.php
Error caching time of next auto publishing event
Could not cache system settings.
Could not cache context settings for web.
Could not cache context settings for mgr.

I just started receiving this error also. My site is not upgraded and I have not made any core changes. Not sure why this just started happening.

Check the permissions on the core/cache directory.

Also, try deleting all files in the core/cache directory.

I had these same errors just pop up and deleting the files in the core/cache directory did the trick.

Thank you.

This occurred out of the box with a fresh 2.2.4 install BTW.

I see these error messages occasionally too. They don't seem to indicate any real problem. I guess your System/Context settings could be out of date if MODX uses the un-updated cached versions of them, but they seldom change, so it's probably not that big a deal.

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