tryin to reply to craiglists for a purchase...will not let me sayin default mail client not intalled properly? how do i fix this or install properly?...thank u

Well, you need an email client first and since you did not tell us what email client (program) you use, we cannot be specific.

See Change the default e-mail program

For specifics, use Google (or favorite search engine) and enter: make [email program name] default mail window 7

make hotmail default mail window 7