Why is my computer suddenly saying Could not reconnect to all network drives?

I think I know what that means, but I don't know why it's doing it. I've had my Lenovo laptop for almost 3 years and never saw that message before. Then yesterday, I had to install a new part on my laptop. I took the whole thing apart, and put it back together, and now this message pops up every time I turn on my computer. Everything works fine. So what does it mean, and how can I fix it?

Go to File Explorer and delete the network drive(s) that no longer work. Re-add them if you want.

Sometimes Windows gets confused which is pretty much why I never bother with automatically mounting network drives because it's just too unstable even when everything is working fine but the drive letters change, and suddenly Windows throws a fit.