Why is iCloud causing Safari and Mail to hang?

Hi,

Only new to the Mac world. I am running a 27in, late 2013 iMac and have just recently updated to OS X 10.9.2. I am also running a Mac Mini Server which is running my mail and websites etc. This has also had the update applied to it and the server app updated to the latest one also.

Since the update I noticed that when starting up Mail it would just hang and not retrieve any mail. Using the Activity monitor it had a number of processes queued (like opening mailboxes and checking mail - usual stuff) but they just sat there not actually processing. Trying to quit the app partially works but eventually you have to use Force Quit to kill the app completely. I could check mail on my iPhone5 no problems so the server was still receiving mail ok.

While trying to find a solution on the net using Safari (and appears to be also with Firefox) all was fine until I navigated to a page with a logon screen. Safari and Firefox would hang and the only option was to Force Quit to get back to using them again.

In relation to my Mail, I decided to check my Internet Accounts under System Preferences. It took forever to load with a message at the top of the screen saying "Loading Internet Accounts" but when it finally did, none of my accounts I had set up were listed there. I went back to the main System Preferences pane and tried again but this time it just stayed there with the "Loading Internet Accounts" message at the top. Again Force Quit was the only option here.

I eventually opened the iCloud Preferences option and noted that it was logged in with the Sign Out option available on this screen. I don't use iCloud as I run it all through my Mac Mini Server and have a NAS backup etc. I chose to Sign Out here. This took forever to be actioned (actually went out for a few hours and it was still working when I came back) but when it did sign me out, I clicked on Internet Accounts and all my accounts were back, I was able to open Mail which connected instantly and retrieved all my mail and was also able to browse using Safari and Firefox to pages with logon prompts and logged in no issues.

It appears iCloud is busting something when it comes to these Applications. I did see an iCloud message once on a logon page which appeared next to a username input field when this first started happening but have not been able to replicate that due to the problems with the browsers hanging.

The problem is after I sign out and then shutdown or restart my iMac (for whatever reason) the next time iCloud is logged back in again and I have to repeat the Sign Out process. Thankfully it signs out in about 20-30 secs but how to I stop it from resigning back in each time the system is rebooted? And is there a known issue with iCloud interacting with these apps (I've not been able to find an exact match to this problem)?

Any help or pointers on this would be greatly appreciated.

Bj