If your username ends with @compuserve.com then you will have to do the following method to cs.com webmail login:
Type on the address bar, webmail.compuserve.com/
Now the site will appear, then enter the email address or username. After that click on the next button.
Then in the required box enter the password and then click on the sign in button.
Also read:
https://saramax092.wixsite.com/expertsbadge/post/does-compuserve-email-still-exist