Follow the given steps to enable or disable archive mailboxes in Office 365 are as follows:
Step 1: First of all, log in to your Office 365 account.
Step 2: Now, click on the Admin icon from the Office 365 menu.
Step 3: After that, click on Show All option.
Step 4: And then, press the Exchange button from the drop-down menu.
Step 5: Furthermore, click on the Recipients option.
Step 6: At last, enable the in-place archive option after clicking on your account.