[Dovecot] quota interferes with dovecot

hi guys,

im having some trouble on my quota.whenever my client reaches the quota, they cant download their mails anymore.

+OK Dovecot 1.0 ready. user test +OK pass testd -ERR [IN-USE] Couldn't sync mailbox. +OK Logged in.

Your server has unexpectedly terminated the connection. Possible causes for this include server problems, network problems, or a long period of inactivity. Account: , Protocol: POP3, Port: 110, Secure(SSL): No, Socket Error: 10053, Error Number: 0x800CCC0F

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