Plesk 7.5.4 for Windows has a bug in this operation: If you DISABLE an account it changes domain acount to domain.d (adds ".d" after domain name). In example: MailEnable: swsoft.com (active account) Then when you Disable this account: MailEnable swsoft.com.d (also its marked as disabled, right?) ok. The problem is when you try to delete disabled accounts. If you try to delete from server any account that has been marked as "DISABLED" before Plesk come back with an error. This erros occurs because Plesk send to MailEnable a command trying to delete "swsoft.com", but it is renamed to "swsoft.com.d". Then everything fails. So, if you're having this problem: Just enable your account and then delete it without problems. This is a simple-solution problem. You should solve it and setup a Patch.