Cannot send emails, reply, or forward.

Last night I suddenly could not send, reply, or forward my emails. The message I get is "A problem occurred while opening this message. A problem occurred.  Please try again. I have done a system restore with no luck. I do not use outlook or hotmail. I do not want to unintall as I am afraid I will loose my contacts and saved emails. I receive my mail from an earthlink and gamail accounts. I have also gone to uninstall programs to do a fix and it tells me it could not fix the problem.