What is 0x8002801D library not registered?
(Exception from HRESULT: 0x8002801D (TYPE_E_LIBNOTREGISTERED)). This is an environmental issue to this machine and the reason is usually a corrupted/invalid registry entry from a Microsoft Office installation, for example, when downgrading Microsoft Office installations.
What is automation error library not registered in Excel?
If you receive the "Library not registered" error in Excel, it means that one or more of the required libraries for Excel are not properly registered. This can happen if you have installed a new version of Excel over an older version, or if certain files become corrupt.