Knowledge Base

How to resolve an internal server error in CodeTwo Backup and CodeTwo Office 365 Migration

Problem:

You are unable to restore or migrate data to the selected Microsoft 365 (Office 365) mailbox. You get the following error:

An internal server error occurred. The operation failed.

or

Unable to upload item - [Item ID]. Error: An internal server error occurred. The operation failed.

Solution:

This error may occur if the mailbox to which you are restoring your backed-up data or migrating data runs out of space. To be able to run the restore or migration job, you can:

  • remove some unnecessary items from the target mailbox (see this article for instructions),
  • increase the storage limit of the target mailbox by assigning a different Microsoft 365 license (learn more),
  • select a different target mailbox.

Was this information useful?