Comparison of EMS for Outlook (COM), EMS for M365 Web Add-in, EMS Web App
Compare reservation features in EMS Web App, EMS for Outlook COM Add-in, and EMS M365 Web Add-in.
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EMS Web App provides browser-based access to reservations, rooms, resources, building schedules, and events.
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EMS for Outlook COM Add-in lets you reserve rooms and resources without leaving classic Outlook for Windows.
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EMS M365 Web Add-in provides EMS reservation features across supported Microsoft 365 Outlook clients.
Feature availability can depend on your EMS configuration, permissions, Outlook client, Exchange environment, and installed integrations.
Use the following tables to see supported features, limitations, and Outlook client differences.
Feature legend
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Yes: Supported
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No: Not supported
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Partial: Support depends on configuration, platform, permissions, or another condition.
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N/A: Not applicable
Reservation workflows
|
Capability |
EMS Web App |
EMS for Outlook COM Add-in |
EMS M365 Web Add-in |
Notes |
|---|---|---|---|---|
|
Create reservation |
Yes |
Yes |
Yes |
|
|
Edit reservation |
Yes |
Yes |
Yes |
Web Process template rules and Outlook or Exchange restrictions can determine which reservation details you can change. |
|
Cancel reservation |
Yes |
Yes |
Yes |
Web Process template rules and Outlook or Exchange restrictions can determine whether you can cancel a reservation. |
|
Create single meeting |
Yes |
Yes |
Yes |
|
|
Create recurring meeting |
Yes |
Yes |
Yes |
Recurring reservations in EMS for Outlook must have an end date. |
|
Request room |
Yes |
Yes |
Yes |
Availability depends on your permissions and process template. |
|
Reserve room |
Yes |
Yes |
Yes |
Availability depends on your permissions and process template. |
|
Book multiple rooms |
Yes |
Yes |
Partial |
Available options depend on your Outlook client and EMS configuration. |
|
Use process templates |
Yes |
Yes |
Yes |
Starting with version 226.3, the Process Template Selector replaces the intent-based workflow in EMS M365 Web Add-in. |
|
Enforce booking rules |
Yes |
Yes |
Yes |
EMS for Outlook reservations follow the rules defined by the applicable Web Process template. |
|
Detect booking conflicts |
Yes |
Yes |
Yes |
|
|
Suggest alternative rooms |
Yes |
Yes |
Yes |
|
|
Resolve recurring conflicts |
Yes |
Yes |
Yes |
|
|
Manage reservation exceptions |
Yes |
Yes |
Yes |
|
|
Move reservation to another room |
Yes |
Yes |
Yes |
|
|
Reschedule from the Outlook calendar |
Yes |
Yes |
Partial |
Outlook for Mac doesn't support automatic detection when you drag an event to another time. Open the event, change the date or time, and save your changes. |
|
Synchronize Outlook changes to EMS |
Yes |
Yes |
Yes |
Requires the configured Exchange integration. |
|
Synchronize EMS changes to Outlook |
Yes |
Yes |
Yes |
Requires the configured Exchange integration. |
Room search and selection
|
Capability |
EMS Web App |
EMS for Outlook COM Add-in |
EMS M365 Web Add-in |
Notes |
|---|---|---|---|---|
|
Search for available rooms |
Yes |
Yes |
Yes |
|
|
View room availability |
Yes |
Yes |
Yes |
|
|
Use schedule or grid view |
Yes |
Yes |
No |
EMS M365 Web Add-in uses list- and card-based room selection. |
|
Use list view |
Yes |
Yes |
Partial |
EMS M365 Web Add-in uses list- and card-based room selection. |
|
Filter by building |
Yes |
Yes |
Yes |
|
|
Filter by area |
Yes |
Yes |
Yes |
|
|
Filter by capacity |
Yes |
Yes |
Yes |
|
|
Filter by room features |
Yes |
Yes |
Yes |
|
|
Filter by room setup |
Yes |
Yes |
Yes |
|
|
Use favorites |
Yes |
Yes |
Yes |
Each EMS application stores its own favorites. |
|
View room details |
Yes |
Yes |
Yes |
|
|
View room capacity |
Yes |
Yes |
Yes |
|
|
View room amenities |
Yes |
Yes |
Yes |
|
|
View room images |
Yes |
Yes |
Partial |
Requires room images to be configured. |
|
View floor plans |
Yes |
No |
No |
Requires floor plans to be configured in EMS. |
|
View building and location details |
Yes |
Yes |
Yes |
Location or space details only. No building details. |
Services and reservation details
|
Capability |
EMS Web App |
EMS for Outlook COM Add-in |
EMS M365 Web Add-in |
Notes |
|---|---|---|---|---|
|
Add services |
Yes |
Yes |
Yes |
|
|
Add resources |
Yes |
Yes |
Yes |
|
|
Request catering |
Yes |
Yes |
Yes |
|
|
Request audiovisual services |
Yes |
Yes |
Yes |
|
|
Request equipment |
Yes |
Yes |
Yes |
|
|
Create service orders |
Yes |
Yes |
Yes |
|
|
Edit service orders |
Yes |
Yes |
Yes |
|
|
Edit resources |
Yes |
Yes |
Yes |
Process template rules can determine which resources you can change. |
|
Complete user-defined fields |
Yes |
Yes |
Yes |
|
|
Answer required booking questions |
Yes |
Yes |
Yes |
|
|
Select event type |
Yes |
Yes |
Yes |
|
|
Assign group |
Yes |
Yes |
Yes |
|
|
Associate contact |
Yes |
Yes |
Yes |
|
|
Enter billing reference number |
Yes |
Yes |
Yes |
|
|
Enter purchase order number |
Yes |
Yes |
Yes |
|
|
Enter cost center information |
Yes |
Yes |
Yes |
Available when configured. |
Online and hybrid meetings
|
Capability |
EMS Web App |
EMS for Outlook COM Add-in |
EMS M365 Web Add-in |
Notes |
|---|---|---|---|---|
|
Create Microsoft Teams meeting |
Yes |
Yes |
Yes |
Requires the Microsoft Teams integration. Licensing is required with Web App |
|
Create Zoom meeting |
Yes |
Yes |
Yes |
Requires the Zoom integration. Licensing is required with Web App |
|
Create Webex meeting |
Yes |
Yes |
Yes |
Requires the Webex integration. Licensing is required with Web App |
|
Support hybrid meetings |
Yes |
Yes |
Yes |
|
Delegation and shared mailboxes
|
Capability |
EMS Web App |
EMS for Outlook COM Add-in |
EMS M365 Web Add-in |
Notes |
|---|---|---|---|---|
|
Use delegated mailbox |
Yes |
Yes |
Yes |
EMS for Outlook supports Outlook delegation assignments. The corresponding EMS everyday user account must have the required delegation settings. For EMS Web App, you need the required Act As permission. |
|
Book for another person |
Yes |
Yes |
Yes |
Requires the required EMS and Outlook permissions. |
|
Use shared mailbox |
Partial |
Yes |
Yes |
Available options depend on your Outlook and Exchange configuration. |
|
Work with EMS Room Sign App |
Yes |
Yes |
Yes |
Reservation changes synchronize through EMS. |
|
Check in to meeting |
Yes |
No |
No |
You can check in through supported EMS applications, but neither Outlook add-in provides a check-in action. |
Exchange and authentication
|
Capability |
EMS Web App |
EMS for Outlook COM Add-in |
EMS M365 Web Add-in |
Notes |
|---|---|---|---|---|
|
Use Exchange Online |
Yes |
Yes |
Yes |
|
|
Use Exchange Server on-premises |
Yes |
Yes |
No |
EMS M365 Web Add-in requires Exchange Online. |
|
Use two-way Exchange integration |
Yes |
Yes |
Yes |
Requires the configured Exchange integration. |
|
Receive real-time availability updates |
Yes |
Yes |
Yes |
|
|
Support time zones |
Yes |
Yes |
Yes |
|
|
Handle daylight saving time |
Yes |
Yes |
Yes |
|
|
Schedule across regions |
Yes |
Yes |
Yes |
|
|
Use OAuth authentication |
Yes |
No |
Yes |
EMS for Outlook COM Add-in uses Outlook authentication. |
|
Use SAML authentication |
Yes |
No |
Yes |
|
|
Use Auth0 authentication |
Yes |
No |
No |
|
Supported Outlook clients
|
Outlook client |
EMS Web App |
EMS for Outlook COM Add-in |
EMS M365 Web Add-in |
Notes |
|---|---|---|---|---|
|
Classic Outlook for Windows |
N/A |
Yes |
Yes |
|
|
New Outlook for Windows |
N/A |
No |
Yes |
|
|
Outlook on the web |
N/A |
No |
Yes |
|
|
Outlook for Mac |
N/A |
No |
Yes |
EMS M365 Web Add-in supports Outlook for Mac starting with version 226.3. |
Deployment
|
Capability |
EMS Web App |
EMS for Outlook COM Add-in |
EMS M365 Web Add-in |
Notes |
|---|---|---|---|---|
|
Cross-platform access |
Yes |
No |
Yes |
|
|
Browser-based deployment |
Yes |
No |
Yes |
|
|
Local installation required |
No |
Yes |
No |
EMS M365 Web Add-in doesn't require a separate installation for each Outlook client. |
|
Microsoft 365 GCC |
N/A |
Partial |
Yes |
Support depends on your deployment. |
|
Microsoft 365 GCC High |
N/A |
Partial |
Yes |
Support depends on your deployment. |
|
Microsoft 365 DoD |
N/A |
No |
Yes |
Requires the supported manifest deployment. |
Choose an EMS application
Choose the application that best fits your workflow:
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EMS Web App: Use for browser-based reservation management, building schedules, event searches, and advanced scheduling options available to your account.
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EMS for Outlook COM Add-in: Use for routine reservations in classic Outlook for Windows.
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EMS M365 Web Add-in: Use for Outlook-based reservations across supported Microsoft 365 Outlook clients.
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EMS Desktop Client: Use when you need additional options for complex reservations or resource management, such as copying a reservation.
Important differences
Outlook for Mac
EMS M365 Web Add-in can't automatically detect a rescheduled event when you drag it to another time in Outlook for Mac.
To reschedule the event:
-
Open the Outlook event.
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Change the date or time.
-
Save your changes.
EMS processes the change after you save the event.
Process templates
-
Starting with version 226.3, EMS M365 Web Add-in uses the Process Template Selector instead of the intent-based workflow.
-
Select the appropriate process template when you create or edit a reservation.
Outlook add-ins
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Don't enable EMS for Outlook COM Add-in and EMS M365 Web Add-in for the same workflow at the same time. The add-ins monitor Outlook calendar activity differently and can cause unexpected behavior.
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Disable EMS for Outlook COM Add-in before you enable EMS M365 Web Add-in for the same users.