Instructions
1) Sign in to Outlook on the web.
2) In the top right-hand corner, click the settings icon (cog).
3) The settings menu contains a search field. Type "mobile" into the field. When the list of results appears, click Manage mobile devices.
4) Hover your mouse pointer over the device for which you wish to cancel the wipe. Then, click the "X" icon on the far right.
5) Click Save to confirm.
Outcome
If you catch the wipe before it happens, the device will not be erased.