Outlook mail problems

Can someone tell me what is going on with Outlook mail on the Vostro 1400 laptops.  The system will all of a sudden not allow you to send or receive mail, there is an error message that pops up; and after using the mail for a few hours when you go to send a message and add an attachment the paperclip icon is not highlighted and you cannot get attachments.  The solution to this has been to shut the laptop down and restart (which is a problem for another forum).  Any thoughts are appreciated.