A docb file extension is related to the XXE software and used for its docbook files.
DOCB file extension - XXE docbook data
What is docb file? How to open docb files?
File type specification:
The docb file extension is associated with the XXE, an app for Microsoft Windows operating system.
The docb file stores docbook created in XXE tool.
The XXE software seems to be obsolete.
This docb file type entry was marked as obsolete and no longer supported file format.
This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.