I'm just learning Kmail and I've identified 2 problems so far. (I've searched the net for answers and have consulted "The KMail Handbook" to no avail -- surprising as these should have been answered a couple of decades ago).

Problem #1: Message file names.
Here is one of my message files:
/home/mark/.local/share/local-mail/inbox/cur/1367208739.R46.Iris:2,S
The problem is the colon character in the file name. Several sources state that many email clients allow the colon to be replaced by another character. I could not find such an option in Kmail. Can you tell me where it is?

Problem #2: End-of-line format.
MS-Windows follows the IBM standard: CR+LF (i.e., 0xD,0xA, which is also the much-older teletype standard).
I believe Apple uses LF only (and ignores CR).
I believe Unix (AT&T) uses CR only (and honors LF by inserting an empty line).
In my opinion, IBM did the sensible thing and AT&T did the nonsensical thing.
How can I force Kmail to use CR+LF?

Thank you.

I suggest to directly install kmail on windows and not use kmail via a virtual machine.

Thank you, vootey. I must install Kmail in Linux inside a virtual machine.