In Outlook Express:
1. Open Outlook Express.
2. From the Outlook Express menu choose Tools -> Accounts.
3. Select the current POP account and click on Properties.
4. On the General tab deselect the option for "Include this account when receiving mail or synchronizing" AND THEN on the Servers tab, deselect the option for "Remember password".
5. Click on OK and Close.
6. Close Outlook Express.
7. Open Outlook Express again and if you are prompted for a password (you shouldn't be) don't give it -- instead click on Cancel. If you are prompted for a password, ensure you have followed the steps above correctly.
8. Now the POP account has been disabled, setup the new IMAP account via Tools -> Accounts.
9. With both the POP account and IMAP account now listed drag the email from the POP account folders to the IMAP account folders.
10. Once you've confirmed all the POP based email has been moved, delete the POP account from Tools -> Accounts.
1. Open Outlook.
2. From the Outlook Express menu choose Tools -> Email Accounts.
3. Make sure the option to "View or change existing e-mail accounts" is selected and then click on Next.
4. Select the POP account and then click on the Change button.
5. Remove the check mark next to "Remember password."
6. Click on Next and then on Finish.
7. Choose Tools -> Options -> Mail Setup and click on Send/Receive.
8. Click on Edit, select the POP account and deselect the option for "Include the selected account in this group". Then click on OK, Close and OK.
9. Close Outlook.
10. Open Outlook again and if you are prompted for a password for that account (you shouldn't be) don't give it -- instead click on Cancel. If you are prompted for a password, ensure you have followed the steps above correctly.
11. Now the POP account has been disabled, setup the new IMAP account via Tools -> Email Accounts.
12. You can now either drag the email from the POP account folders to the IMAP account folders or use the File -> Import/Export utility to import the POP based PST file into the IMAP account.
13. Once you've confirmed all the POP based email has been moved, delete the POP account from Tools -> Email Accounts.
Migrating from POP3 to Outlook Connector:
If you are converting from POP3 to Outlook Connector, it's recommended to follow the Outlook steps 1-12 above and initially migrate the email from the POP3 PST as indicated.
Once this has been done create a new Outlook Profile and configure the Outlook Connector account as the only account in the profile and confirm all email is correctly loaded into the new Outlook Connector Account.
Finally, from the Outlook menu choose File -> Open -> Outlook Data File and open the original POP3 PST file. You can then move/drag any existing calendar, contacts or task entries from the POP3 PST file into the Outlook Connector account before closing the PST.
Possible issues to note:
1. Whilst POP3 PST based email accounts support the use of characters such as \ : & / in email folder names, IMAP and Outlook Connector accounts don't. This is because this folder will be created as a Windows Folder in the users mailbox on the server. For this reason, it's important these folder names are changed before you move/drag the folders between the accounts or any import via the File -> Import/Export utility in Outlook.
2. An import of a PST into an IMAP account can sometimes fail and this is often due to an element of corruption in the PST file itself. Microsoft supply a PST repair tool with Outlook called scanpst.exe which you can use to scan and fix these errors. Please see http://support.microsoft.com/kb/272227/en-us for details.