What is the UID SORT Error?

The UID SORT error may occur when you log into a mailbox using the Roundcube webmail client. This error message is displayed in the bottom right corner of the interface:

UID SORT: Internal Error occurred. Refer to server log

This error generally indicates issues with your mailbox's storage capacity or plan limits.

Causes of the UID SORT Error

There are two common reasons for encountering this error:

1. Exceeded Mailbox Disk Space Quota

If your mailbox disk space quota is exceeded, you can check your mailbox disk usage by navigating to:

Email → Mailboxes → Click on your mailbox name

If the disk space quota is exceeded, it will display:

Disk Space: 10.0 GB (100%) of 10.0 GB used

Solution:

• Go back to your email accounts list.
• Click on <...> next to your mailbox under the Mailbox Limits column.
• Temporarily increase the mailbox disk quota.
• Log back into your mailbox and delete some emails to free up space.

You can also download your messages using POP3 (without leaving a copy on the server) or delete messages using an IMAP account via a mail client like Outlook or Thunderbird.

2. Exceeded Plan Mail Storage

If your account has exceeded the allocated mail storage for your hosting plan, you can verify this at:

Account Usage → Mail Storage

Solution: Upgrade your mail storage plan to accommodate your needs. If your mail storage is exceeded because some mailboxes are left unattended, please contact us for a list of the largest mailboxes and assistance with deleting messages.

Important Note

Keep in mind that deleting a mailbox from the Email Accounts section does not remove the mailbox directory, which serves as a fail-safe feature for your convenience. If you need a mailbox to be completely deleted, please submit a support ticket.

Conclusion

By understanding the causes of the UID SORT internal error and taking the appropriate actions to manage your mailbox storage, you can resolve the issue efficiently and ensure smooth email operations.