Time Zone is UTC -8 when scheduling a meeting from either the teams calendar or outlook calendar, how to resolve this issue

Hello @Nash Teh,  

Thank you for responding.  

I truly appreciate the amount of effort you and your team have put into testing this issue across multiple devices and platforms.  

From everything you’ve described, this behavior is definitely not normal. It’s unusual and inconsistent, and it doesn’t match how Outlook or Teams time‑zone synchronization is supposed to work under standard conditions. 

So, I highly recommend raising a support ticket to our higher technical. I believe your case may require a deeper investigation from Microsoft’s advanced technical support team, as they have access to backend diagnostic tools and tenant‑level data. 

(If you are not the global admin, please kindly ask your IT Admin to do it for you)     

• To create a Support ticket, you can go to: Microsoft 365 Admin Center.              
• When you click Help & Support in the bottom-left corner, a Support Assistance panel will appear.      
• In the text box, you can type: "request an agent to contact me via email or phone" and press Enter.      
• After that, please look at the bottom-left corner of the panel. You will see a blue link that says, "Contact Support"; you click on it.      

• You will then have two options: Support via phone or via email. You can choose Email.      

Please follow this article: Get support - Microsoft 365 admin | Microsoft Learn    

When the ticket is opened, a support engineer can start a remote session to investigate the issue, review the back-end settings, and optionally run a sync tool to resolve the issue.        

I truly hope you’ll be assisted soon by our dedicated technical team. And if you receive any updates or insights, please feel free to reply here.          

Looking forward to hearing from you!

Since this forum is a public platform, I have modified your question to hide your personal privacy. For future posts, kindly avoid sharing personal or organizational information to protect your data.     

Hello @Nash Teh,  

Thank you for reaching out to the Q&A forum and Happy New Year 2026!

For your situation, I will explain detail: 

• Outlook and Teams do not rely solely on the operating system’s time zone settings. Instead, they pull the time zone from the user’s account settings in Exchange Online or Outlook Web App (OWA).  
• This means that even if the computer is set correctly, if the account configuration still stores an incorrect time zone, the calendar will display that time zone. 

I would you like to reconfirm this point: 

When you said you checked the Mac and Windows settings, did you check your own devices or the devices of those attendees who are showing UTC-8? 

Since you mentioned that only some attendees show correctly, the issue is likely not on your device, but rather with the affected attendees’ account settings. 

Additionally, you can ask affected attendees to check in Outlook Web (OWA): 

• They go to Settings => View all Outlook settings => General => Language and time. 
• Then, they set the time zone to (UTC +08:00) Kuala Lumpur, Singapore. 

• When they change the time zone, Outlook will prompt: “Do you want to update meeting hours to the new time zone?”, please click Yes, update (Even if the correct time zone is already displayed) 

If the problem continues, to support you better, please provide me more detail: 

1. For the attendees who are showing UTC-8, are they in the same tenant as you? 
2. If yes, could you please share screenshots from the Outlook settings for two cases: one attendee whose time zone is correct and another attendee who shows UTC-8. 

Please understand that our initial response may not always resolve the issue immediately. However, with your help and more detailed information, we can work together to identify the root cause and find a solution.           

Looking forward to hearing from you!   

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