All systems are operational
Maintenance
US IMAP email server downtime

On 22 July 2026 at 10:00 am US/Central time (UTC -5) one of our US IMAP email servers will be shut down for infrastructure maintenance. The server will be offline during the maintenance and the expected downtime is 6 hours.

Affected customers will be notified individually via email.

No incoming mail will be lost while the server is offline. Mail that arrives during the maintenance will be deferred and delivered once the mail server is back online.

We realize that the timing of this relocation is not ideal. If you have business-critical mailboxes and would like them to be available during the maintenance then please email support@opalstack.com or reply to this message to make arrangements to have your mailboxes migrated to a different IMAP server prior to the scheduled maintenance date.

If you have any questions or concerns regarding this maintenance then please email the Opalstack support team for assistance.

Past Incidents

19th May 2021

No incidents reported

18th May 2021

No incidents reported

17th May 2021

Email: USA Temporary SSL problem in US mail system

At approximately 06:00 UTC on 17 May 2021 we inadvertently pushed the wrong set of SSL certificates to our US mail system.

Customers who attempted to access the mail system during that period may have seen certificate warning messages and would not have been able to access their mail.

The problem was fixed approximately 30 minutes later and the mail system has been working normally since that time. No incoming or outgoing mail was lost during the incident.

If you are still seeing a certificate error while attempting to use the US mail system then please restart your mail client and/or reboot your computer. If the problem persists then please contact Opalstack support for assistance.

16th May 2021

No incidents reported

15th May 2021

No incidents reported

14th May 2021

No incidents reported

13th May 2021

No incidents reported

12th May 2021

Email: Germany German SMTP IP range on MS block list

We've received some reports that outlook.com and other Microsoft mail services are blocking smtp.de.opalstack.com.

We're investigating now and will follow up when we have more info.

  • Microsoft is now accepting mail from smtp.de.opalstack.com.

  • We've identified and corrected the cause of the block, and have passed our findings along to Microsoft with a request to delist the German SMTP address.

    We'll update this post when Microsoft have confirmed that the server is no longer on the block list.