It is possible that your account settings in MSN are already corrupted. I will be providing the steps to fix this. Before you follow them, please make sure that you back up all e-mails that are stored in 'Folders in your Computer' on your MSN making sure that we won't lose anything in the process.

Please follow the Method 1 steps on this link to back up the email messages: http://answers.msn.com/solution.aspx?solutionid=d830f08c-414d-49ae-91cb-df58aa44832f  If you have several e-mail accounts, sign in on the other email address then follow the steps on the link but change the last part of the file name so that you can identify the backed up email. For example, instead of leaving it as MSN_Mail.msnbak you can change it to MSN_(e-mail address).msnbak.

Once the email messages are backed up, please follow the steps on this link to perform CTRL+SHIFT+F11 which refreshes the account settings: http://answers.msn.com/thread.aspx?threadid=d2de6731-17a3-41fd-9fde-c9185947dfc5

If the same issue persists, the email synchronization file (SDF) that is found on the computer has gotten corrupted causing MSN not to be able to download the email messages from the email server. Please follow the steps on this link so the file can be replaced: http://answers.msn.com/thread.aspx?threadid=1e24ba67-43eb-44af-a24d-8462d528464b

Feel free to reply to this post for any questions and feedback.

Thanks!