Using Microsoft 365

Practical guide for working with Outlook, OneDrive, Calendar, Teams, and SharePoint through Fp Switchboard.

Quick Tips

• Use me for authenticated user or full UPN (user@domain.onmicrosoft.com)
• All dates must be ISO 8601 with timezone (2024-03-15T09:00:00Z)
• Attachments under 4MB inline, over 4MB require upload session
• Rate limit: 10,000 requests/10 min per mailbox
• Use @odata.nextLink for pagination

Common Gotchas

User ID vs UPN vs Mail Critical

Graph API accepts user ID (GUID), userPrincipalName (UPN), or me. Email does not always equal UPN.

	Example
Wrong	/users/john@company.com/messages
Correct	/users/john.smith@company.onmicrosoft.com/messages or /me/messages

ISO 8601 with Timezone Required Important

All datetime values must be ISO 8601 with timezone. Calendar events are especially sensitive.

	Example
Wrong	2024-03-15 09:00
Correct	2024-03-15T09:00:00Z or 2024-03-15T09:00:00-05:00

Per-Mailbox Throttling Critical

Mail API throttles per-mailbox (10,000 requests/10 min). Bulk operations hit limits fast.

	Example
Wrong	Looping through 1000 emails sequentially
Correct	Use $batch endpoint (max 20 requests) or pagination with $top

Attachment Upload Size Limits Important

Attachments under 4MB can be added inline. Over 4MB requires createUploadSession. Max file size 150MB.

Drive vs DriveItem Important

A Drive is a container (OneDrive, SharePoint library). DriveItem is a file/folder within it.

	Example
Wrong	GET /me/drive to get file content
Correct	GET /me/drive/items/{item-id}/content for file content

Microsoft Teams Specifics

Team ID = M365 Group ID

Every Team has an underlying Microsoft 365 Group with the same GUID.

Channel Types

• Standard — visible to all team members
• Private — members only, requires explicit membership check
• Shared — cross-organization, uses different endpoints

Chat Message Threading Critical

Replies go to specific message, not channel root.

	Example
Wrong	POST /teams/{id}/channels/{id}/messages for reply
Correct	POST /teams/{id}/channels/{id}/messages/{messageId}/replies

Meeting Scheduling

Online meetings are created via Calendar API, not Teams directly.

	Example
Wrong	POST /teams/{id}/meetings
Correct	POST /me/events with isOnlineMeeting: true

Multi-Step Patterns

Send Email with Attachment

1. POST /me/messages to create draft
2. POST /me/messages/{id}/attachments for small files
3. Or use createUploadSession for large attachments
4. POST /me/messages/{id}/send to send

Schedule Teams Meeting

1. POST /me/events with isOnlineMeeting: true
2. Set onlineMeetingProvider: "teamsForBusiness"
3. Meeting URL returned in onlineMeeting.joinUrl
4. Attendees auto-invited via calendar invite

ID Format Reference

ID Type	Format	Example
User ID	GUID	a1b2c3d4-e5f6-7890-abcd-ef1234567890
Message ID	Base64-encoded string	AAMkAGI1...
Drive Item ID	Alphanumeric	01BYE5RZ6QN...
Team/Group ID	GUID	Same as above
Channel ID	Encoded string	19:abc123...@thread.tacv2

Example Prompts

• “Send an email to the project team about the deadline”
• “List my unread Outlook messages”
• “Create a Teams meeting for Friday at 3pm”
• “Search OneDrive for the presentation deck”
• “List my calendar events for next week”

Rate Limits

Service	Limit
Outlook Mail	10,000 requests/10 min per mailbox
Teams Messages	4 messages/second per channel
OneDrive	10,000 API calls/10 min
SharePoint	Varies, 429 with Retry-After header