How to completely change my eM Client setup

My service provider is telling me to change to a completely different webmail address, inbound & outbound links, port numbers etc, etc.  Some of these parameters are selected automatically by eM Client on first setup and I can’t find how to reconfigure them.  Any suggestions ? (Other than archiving all my emails, destroying eM Client and then trying to completely start afresh !) 

Go to Menu > Tools > Accounts and click on the account you want to re-configure. To the right are IMAP and SMTP tabs where you will find the items you need to change.

Be aware that if you are changing the host/server address, you may lose all your IMAP messages. So before making any changes, you should export all your messages using Menu > File > Export > Export messages to eml. You can select multiple folders and the folder structure will be maintained. 

Once the account is re-configured, you can import your messages back into the folders if they are no longer there.

When re-configuring the account, make sure you have the correct security policies for the ports you were given.

Port 587 = Force usage of SSL/TLS
Port 25 = Use SSL/TLS if available
Port 465 = Use SSL/TLS on special port (legacy)

Port 993 = Use SSL/TLS on special port (legacy)
Port 143 = Use SSL/TLS if available

Port 995 = Use SSL/TLS on special port (legacy)
Port 110 = Use SSL/TLS if available

Thanks for the update. I had already found all the menu items mentioned, but these do not include al the sections that have to be updated. The reply indicates that there will be IMAP & SMTP tabs in the account menu - not in my case, I’m currently on POP3 and so switching from POP3 to IMAP is one of the changes that appears to have no means of access or implemention. Above that again in the setup hierarchy is the internet webmail address used to access the email server. I seem to remember that eM Client searches for this automatically, so this is not entered at all. However my service provider had both legacy POP3 emails on one server and current emails (MIME) on a different server. They’ve now amalgamated everything on a new server and recommend all users to change to the new server.  How on earth do I configure eM Client to use this new server when it is a parameter over which I have no control ?  As far as I can see, the only possibility is erase everything, setup a new eM Client access and hope that it can automatically find the right server

Unfortunately you cannot just change the account from POP3 to IMAP because they have different message stores. POP3 stores the messages on your computer while IMAP stores the messages on a server.

What you need to do in that case is create a new account, setting it up using the Automatic Setup, or if that does not work set it up manually. Please see the Help File (F1) if you have issues [setting up an account manually](| _____ 3).

Once the IMAP account is setup, you can move the messages from the POP3 folder to the IMAP folders and then delete the POP3 account.