Most users switch to new mobile devices or add new ones. Over a period of time, your Exchange mailbox may have quite a few mobile devices. If you’re not using a smartphone or other Exchange ActiveSync (EAS) device (including Windows 8/Windows RT tablets, Apple iPad or other iOS devices), you can remove it from your account using Outlook Web App. You can also wipe an existing mobile device, as long as it’s still active and syncing mail.
Office 365 and more than 10 ActiveSync devices
If your mailbox is in Office 365, it has a limit of 10 ActiveSync device partnerships at the same time. If you keep accumulating device partnerships and not remove old devices that you no longer have, you’re prevented from adding more than 10 devices. When trying to add the eleventh ActiveSync device, you get an error message on the mobile device. You also continue to get daily email alerts with the subject: “Error with your mobile phone partnership” with instructions to remove existing ActiveSync devices from your account.
To remove an Exchange ActiveSync device from your account:
Go to Options > See all options
- Select Phone. The Mobile Phones tab shows a list of all Exchange ActiveSync devices connected to your account, including mobile phones and tablets.
Select the device you want to remove and click Delete. The Last Sync Time field shows you the last time a device synchronized.
Before disposing off a phone, make sure you remove your data from the phone. You can use the Wipe Device option fromt Outlook Web App to wipe device data. Additionally, most mobile phones and other mobile devices have an option to reset the device to factory settings.