Microsoft Bookings Ignores Outlook Calendar Availability and Allows Double Booking

Question

Microsoft Bookings Ignores Outlook Calendar Availability and Allows Double Booking

Harald Eisenhauer 0

Hello Microsoft Support,

I am experiencing an issue with Microsoft Bookings where appointments can be booked with me even though my Outlook calendar is fully blocked as Busy.

Current configuration:

Staff member availability: Bookable when staff are free
Events on Office calendar affect availability: Enabled
My Microsoft 365 Outlook calendar is blocked for the entire week with events marked Busy
I only have one work calendar/mailbox
The booking service is assigned to multiple staff members

Issue: Despite my Outlook calendar showing no availability, the public Bookings page displays all time slots as available and customers can book appointments that are then assigned to me.

To troubleshoot, I:

Verified that all calendar events are marked as Busy.
Confirmed that Events on Office calendar affect availability is enabled.
Confirmed the service is configured as Bookable when staff are free.
Changed my availability to Not bookable, saved, then changed it back.
After doing so, the public booking page temporarily showed staff availability as Loading, then eventually displayed all time slots as available again.

I also checked the Microsoft 365 Service Health dashboard and all services are reported as healthy.

Based on the configuration, I would expect Bookings to block all appointments assigned to me while my calendar is marked busy. Instead, Bookings appears to be ignoring my Outlook free/busy information.

Could you please investigate whether:

There is a synchronization issue between Bookings and Exchange Online for my account.
The staff member record has become disconnected from the mailbox.
There is a known issue affecting free/busy lookups in Microsoft Bookings.

Please let me know what diagnostic information would be helpful (tenant ID, booking mailbox, logs, screenshots, etc.).

Thank you.

Kind regards,

Harald

FlorianFry-5862 0 Zuverlässigkeitspunkte

2026-08-12T15:10:17.1466667+00:00

Dear Microsoft Support,

We had almost the same problem.

We have a Bookings service to which exactly one employee is assigned.

The service is bookable when the employee is available.

The following option is enabled for the employee: “Events in the Office calendar affect availability.”

Although appointments were blocked in the employee’s Outlook calendar, customers were still able to book those appointments. This caused major difficulties.

It now appears that Outlook availability is being taken into account again.

Question: Is there official confirmation that this was an issue and that it has been resolved?

Best regards,
Florian
Jade Ng 16,120 Zuverlässigkeitspunkte Externe Microsoft-Mitarbeiter Moderator

2026-08-13T05:44:10.9133333+00:00

Dear FlorianFry-5862,

Thank you for sharing your experience.

As mentioned in my previous response, I recommend reviewing the validation steps already discussed, particularly testing whether removing and re-adding the affected staff member changes the behavior.

If the issue reoccurs or is still intermittently reproducible, I recommend opening a support ticket so the Product Team can investigate the behavior directly within your tenant and determine whether there are any underlying service issues affecting Bookings availability.

Thank you for your valuable time and cooperation.
FlorianFry-5862 0 Zuverlässigkeitspunkte

2026-08-13T11:08:29.4866667+00:00

Dear Jade,

Okay, so

there are

at least

four different tickets

describing similar issues

with Microsoft Bookings. I don’t know what you think about this, but common sense tells me: If four people from all over the world independently report a similar issue, it’s more likely to be a technical problem on Microsoft’s end than a misconfiguration or a tenant-specific issue on the customer’s end. I simply wanted confirmation of this from Microsoft—and ideally, official confirmation that the issue has been resolved. Otherwise, we’d have to keep an eye on the issue and actively monitor whether it reoccurs or not.

But I can’t find any such official information, and that’s exactly my point. Furthermore: In my opinion, it’s pointless to tell every single customer to do this or that to test and fix the problem (as happened in the four tickets mentioned) when it can really only be fixed by Microsoft itself.

Instead, everything seemed to be fine with Bookings in the Microsoft 365 Admin Center over the past two to three weeks, even though it wasn’t.

It’s really not my intention to be harsh; I was just hoping for a little official information, rather than having customers burdened with something they have no control over.

Kind regards,
Florian
Jade Ng 16,120 Zuverlässigkeitspunkte Externe Microsoft-Mitarbeiter Moderator

2026-08-14T04:37:33.3533333+00:00

Dear FlorianFry-5862,

I completely understand your concern when multiple customers independently report similar behavior across different environments.

Unfortunately, as a forum moderator, I do not have visibility into Microsoft's internal service health investigations, backend telemetry, engineering reports, or product team communications. My primary role is to provide guidance based on the information available in the forum and help users take the next appropriate troubleshooting steps.

For this reason, when similar issues are reported, I often recommend verification and troubleshooting steps or suggest opening a support ticket. These steps are not intended to place responsibility on the customer. Rather, they help gather the information required for Microsoft's support engineers to determine whether the behavior is caused by configuration, synchronization, tenant-specific conditions, or a broader service-side problem.

Deeper investigation of potential backend issues requires access to internal diagnostic tools and systems that are only available to Microsoft Support and, when necessary, the Product Engineering team. This is why I recommended those steps and suggested engaging Microsoft Support. They are the teams that can perform advanced diagnostics, review backend logs, and escalate the matter to the product developers if a service issue is suspected.

While I cannot provide official confirmation regarding any internal investigation or service incident, I genuinely appreciate your feedback and understand your perspective. My goal is always to help point customers toward the most effective path to obtain a definitive answer and resolution.

Thank you again for your understanding.

1 Antwort

Ihre Antwort

FlorianFry-5862 0 Zuverlässigkeitspunkte

2026-08-12T15:10:17.1466667+00:00

Dear Microsoft Support,

We had almost the same problem.

We have a Bookings service to which exactly one employee is assigned.

The service is bookable when the employee is available.

The following option is enabled for the employee: “Events in the Office calendar affect availability.”

Although appointments were blocked in the employee’s Outlook calendar, customers were still able to book those appointments. This caused major difficulties.

It now appears that Outlook availability is being taken into account again.

Question: Is there official confirmation that this was an issue and that it has been resolved?

Best regards,
Florian
Jade Ng 16,120 Zuverlässigkeitspunkte Externe Microsoft-Mitarbeiter Moderator

2026-08-13T05:44:10.9133333+00:00

Dear FlorianFry-5862,

Thank you for sharing your experience.

As mentioned in my previous response, I recommend reviewing the validation steps already discussed, particularly testing whether removing and re-adding the affected staff member changes the behavior.

If the issue reoccurs or is still intermittently reproducible, I recommend opening a support ticket so the Product Team can investigate the behavior directly within your tenant and determine whether there are any underlying service issues affecting Bookings availability.

Thank you for your valuable time and cooperation.
FlorianFry-5862 0 Zuverlässigkeitspunkte

2026-08-13T11:08:29.4866667+00:00

Dear Jade,

Okay, so

there are

at least

four different tickets

describing similar issues

with Microsoft Bookings. I don’t know what you think about this, but common sense tells me: If four people from all over the world independently report a similar issue, it’s more likely to be a technical problem on Microsoft’s end than a misconfiguration or a tenant-specific issue on the customer’s end. I simply wanted confirmation of this from Microsoft—and ideally, official confirmation that the issue has been resolved. Otherwise, we’d have to keep an eye on the issue and actively monitor whether it reoccurs or not.

But I can’t find any such official information, and that’s exactly my point. Furthermore: In my opinion, it’s pointless to tell every single customer to do this or that to test and fix the problem (as happened in the four tickets mentioned) when it can really only be fixed by Microsoft itself.

Instead, everything seemed to be fine with Bookings in the Microsoft 365 Admin Center over the past two to three weeks, even though it wasn’t.

It’s really not my intention to be harsh; I was just hoping for a little official information, rather than having customers burdened with something they have no control over.

Kind regards,
Florian
Jade Ng 16,120 Zuverlässigkeitspunkte Externe Microsoft-Mitarbeiter Moderator

2026-08-14T04:37:33.3533333+00:00

Dear FlorianFry-5862,

I completely understand your concern when multiple customers independently report similar behavior across different environments.

Unfortunately, as a forum moderator, I do not have visibility into Microsoft's internal service health investigations, backend telemetry, engineering reports, or product team communications. My primary role is to provide guidance based on the information available in the forum and help users take the next appropriate troubleshooting steps.

For this reason, when similar issues are reported, I often recommend verification and troubleshooting steps or suggest opening a support ticket. These steps are not intended to place responsibility on the customer. Rather, they help gather the information required for Microsoft's support engineers to determine whether the behavior is caused by configuration, synchronization, tenant-specific conditions, or a broader service-side problem.

Deeper investigation of potential backend issues requires access to internal diagnostic tools and systems that are only available to Microsoft Support and, when necessary, the Product Engineering team. This is why I recommended those steps and suggested engaging Microsoft Support. They are the teams that can perform advanced diagnostics, review backend logs, and escalate the matter to the product developers if a service issue is suspected.

While I cannot provide official confirmation regarding any internal investigation or service incident, I genuinely appreciate your feedback and understand your perspective. My goal is always to help point customers toward the most effective path to obtain a definitive answer and resolution.

Thank you again for your understanding.

Answer 1

Disclaimer: This platform is in German. However, I noticed that your message was written in English, so I will respond in English to ensure clarity and provide better assistance.

Dear @Harald Eisenhauer,

Based on your configuration, Microsoft Bookings should normally respect your Exchange Online free/busy information when "Events on Office calendar affect availability" is enabled and the service is configured as "Bookable when staff are free."

Since you have already verified the primary configuration settings and your Outlook calendar is blocked with events marked Busy, the behavior you are seeing may indicate one of the following:

A synchronization issue between Bookings and Exchange Online free/busy data.
A problem with the staff member's Bookings profile or calendar synchronization.
A broader service-side issue affecting Bookings availability calculations.

To help further isolate the issue, could you please confirm the following?

Does the issue affect only your staff profile, or do other staff members in the same Bookings calendar experience the same behavior?
If possible, please take a screenshot and share it with me.

I would also recommend testing whether removing and re-adding the affected staff member temporarily changes the behavior. Additionally, I found a recent report from another post describing similar symptoms where Bookings displayed available slots despite staff calendars being unavailable: Bookings allowing people to book when staff are not available on their personal calendar

If the issue persists after the above validation, the best approach is to submit a support ticket to the Microsoft team. They have access to your account and can call you directly to assist with the process.

Here’s how you can raise a support request ticket to the support team:

Open the Microsoft 365 Admin Center, then click Help & Support located in the bottom-right corner of the screen.
In the search bar, type “your issue” > Enter > scroll down, and click on "Get Help" > "Contact support".
Choose your preferred contact method, fill in the required details, and then click Contact Me to submit your request.

I appreciate your cooperation and look forward to your update.

Jade Ng 16,120 Zuverlässigkeitspunkte Externe Microsoft-Mitarbeiter Moderator

2026-08-03T00:33:35.5566667+00:00

Dear @Harald Eisenhauer,

I just wanted to check in and see if you have any updates or additional information you’d like to share regarding your situation. If there's anything new or if you need further assistance, please don’t hesitate to let me know.

Looking forward to hearing from you!