Email - Permission Trouble

[aznium]

I can not send or receive email.

I can not create email accounts through plesk.

I can not even update plesk.

I have not touched any of plesk files. It happened sportatically.

For a brief period. Email was fine but then it died randomly.

Error: Unable to update the mail name properties:mailmng failed: mailmng: Unable to open file "/usr/local/psa/var/lock/files/2b41cfc09d5551bc725fc1f754631002": Permission denied.
System error 13: Permission denied
mailmng: Error occurred while locking the file /var/qmail/users/assign: Permission denied

System error 13: Permission denied
mailmng: Unable to remove record for williamchan from assign file
System error 13: Permission denied
mailmng: Unable to open file "/usr/local/psa/var/lock/files/2b41cfc09d5551bc725fc1f754631002": Permission denied.
System error 13: Permission denied
mailmng: Error occurred while locking the file /var/qmail/users/assign: Permission denied

System error 13: Permission denied
mailmng: Unable to open file "/usr/local/psa/var/lock/files/2b41cfc09d5551bc725fc1f754631002": Permission denied.
System error 13: Permission denied
mailmng: Error occurred while locking the file /var/qmail/users/assign: Permission denied

System error 13: Permission denied
mailmng: Unable to remove williamchan mailbox record from assign file
System error 13: Permission denied
mailmng: Unable to open file "/usr/local/psa/var/lock/files/05a614fac33d3831305fdb55b2be8e8a": Permission denied.
System error 13: Permission denied
mailmng: Error occurred while locking the file /var/qmail/users/poppasswd: Permission denied

System error 13: Permission denied
mailmng: Unable to remove williamchan mailbox record from password file

System error 13: Permission denied
mailmng: Unable to add record for williamchan to assign file
System error 2: No such file or directory

thx if anyone can help me