any other accessible email client for linux?

[Linux for blind general discussion]

Try removing its configuration profile from a terminal.
rm -R ~/mozilla/seamonkey
should do it. Then run seamonkey mail again and you should be able to see the 
regular welcome screen. Just be sure to run seamonkey mail rather than seamonkey 
web browser, or if you have only one seamonkey entry, you may want to explicitly run
seamonkey --mail
from your run window. That on its own may work without removing your 
configuration folder, but there is no harm in removing it.
~Kyle