over the years I have accumulated email accounts with different organisations (educational institutes, for example), some of which have been retired by the respective organisation or will be in the future. KMail is configured to store all mail locally, for searching at a later time.
When an account is retired by the provider I want to keep being able to search through the mail in the familiar interface, but would also like to stop KMail from trying to connect and authenticate to the server which once hosted the account. Trying to disable all automatic connection similar to what was done here: Can’t stop receiving Mails is not enough, KMail still tries to authenticate at startup, resulting in unnecessary traffic and annoying notifications.
I’d be grateful for any ideas on how to retire accounts in a way that keeps the locally stored mail available for reference.
Get another version of KMail, change its config directory, then use a firewall to block it from accessing the internet. I suggest this not knowing if KMail allows you to change its config directory, as I don’t use it myself.
As for error messages/notifications about not being able to access the internet, I think those are hardcoded, so unless you know how to code…
Another option is to check if there is an extension for this (blocking internet access and/or notifications) in Thunderbird. It’s not KMail, I know, but you have a very specific use case, so you may need a specific tool.
Hm, using a different instance of a mail application without internet access could work, but it would divide the unified inbox and probably still generate unwanted notifications (which I could disable from the Plasma side).
Transferring the mail of already dead accounts to another application might also be challenging.
Overall, I think I prefer dealing with the notifications and the traffic over having two separate mail applications for now.