Hi Mansi Gusain,
Thanks for reaching out to Microsoft!
To set the timezone to Central European Standard Time (CEST) in the Microsoft Graph API, you should use the timezone identifier for CEST, which is "Central European Standard Time".
When setting up an Outlook client, the user selects the preferred time zone from this supported list. You can subsequently get the preferred time zone by getting the user's mailbox settings.
Use the Prefer: outlook.timezone
header to specify the time zone for the start and end times in the response:
Prefer: outlook.timezone="Central Europe Standard Time"
Hope this helps.
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