Cheers Bill, I&#039;m running about like an idiot just trying to get stuff cleared up before I go on holiday next week. Anyway, the line below:<BR><BR>strLDAP = "LDAP://" & Application("mailserver") & "/cn=" & strUsername & ",cn=Recipients,ou=xxxxx,o=xxx"<BR><BR>was causing the problems. For some reason, the Application("mailserver") was returning an empty string on some occasions, so I&#039;ve fixed that by hard-coding it in for now.<BR><BR>Cheers