Error when replying to a post

Hi - perhaps someone can help me (noob)

When registered members of my forums fill out a reply and hit the reply button, they get this error

 Microsoft VBScript runtime error '800a0046'

Permission denied

/axaesque/forum/send_mail_function.inc, line 162

They have to refesh and hit BACK before returning to view their completed post.

[edit] - figured out the one above - thanks

Also - can I enlarge the size that the avatars are displayed at ?

thanks for any help