Update!
Grrr... This creepy message is back again, I'm sick of it Apple!
"This mac can't connect to iCloud because of a problem with..."
"Open iCloud preferences to fix this problem"
Grrr... Apple, I've had this problem for weeks now, I've reset the password, nothing works, each time I start again, here comes the message.
Finally today I was able to get rid of it by doing the following:
1) Start the Mac,
2) Go to System Preferences Panel, iCloud and Sign Out,
3) Make sure you are keeping things local if you need to, else all the iCloud related files will be erased from your computer, be careful here, when you are logged out of iCloud,
4) Restart the Mac,
5) The stupido message should not appear this time -duh! You are logged out of iCloud,
6) Go to System Preferences Panel, iCloud and Sign In,
7) Restart the Mac to see if you finally made it.
For me that did the trick, pfff.
Update: Nooooo! It's back!!! What a pain this is.
