How to uninstall Signature 365 from your Microsoft 365 tenant

To uninstall Signature 365 from your Microsoft 365 tenant, you first need to deactivate and delete the Signature 365 transport rule.

Note if you just want to temporarily disable email flow to Signature 365, you can simply deactivate the Signature 365 transport rule.

Deactivating the transport rule

To deactivate the Signature 365 transport rule, follow these steps:

1. Log on to the Microsoft 365 admin center as a Global Administrator
2. Open the Exchange admin center
3. Go to Mail flow, then select Rules
4. Select the Send to Signature 365 for signature injection rule
5. Unselect the checkbox to deactivate the rule

The transport rule will now be deactivated. To reactivate it, simply click the checkbox again.

Deleting the transport rule

To permanently delete the Signature 365 transport rule, follow these steps:

1. Within the Exchange admin center, go to Mail flow, then select Rules
2. Select the Send to Signature 365 for signature injection rule
3. Click the trashcan icon above the transport rule to delete it
4. In the warning message that appears, click Yes to permanently delete the transport rule

Deactivating the connectors

To deactivate the Signature 365 connectors, follow these steps:

1. Within the Exchange admin center, go to Mail flow, then select Connectors
2. Select the Receive from Signature 365 connector
3. Click the turn it off link under Status, or in the New Exchange admin center, click the pause icon
4. Repeat the same steps to deactivate the Send to Signature 365 connector
   
   

   Warning

   You can only deactivate the Send to Signature 365 connector if you have deleted the transport rule. You cannot deactivate this connector if you only deactivated the transport rule.

Deleting the connectors

To permanently delete the Signature 365 connectors, follow these steps:

1. Within the Exchange admin center, go to Mail flow, then select Connectors
2. Select the Receive from Signature 365 connector
3. Click the trashcan icon above the connector to delete it
4. Repeat the same steps to delete the Send to Signature 365 connector
   
   

   Warning

   You can only delete the Send to Signature 365 connector if you have deleted the transport rule. You cannot deactivate this connector if you only deactivated the transport rule.

Deleting applications

Signature 365 will create one or more of the following applications in your Azure tenant:

• Signature 365
• Signature 365 Setup
• Signature 365 Sent Items Update

To remove the Signature 365 Azure applications, follow these steps:

1. Log on to the Azure portal as a Global Administrator
2. Go to Azure Active Directory, then select Enterprise applications
3. In the search box, type Signature 365 to filter to only show Signature 365 applications
4. For each Signature 365 application, repeat the following steps 5-8
5. Click the application to remove
6. In the left-hand pane, under Manage, select Properties
7. From the Properties page, click Delete
8. In the dialog that appears, confirm you want to delete the application