A xos file extension is related to the Xaos Tools bitmap image file format. Most likely some old format without support.
XOS file extension - Xaos Tools bitmap image
What is xos file? How to open xos files?
File type specification:
The xos file extension is associated with Xaos Tools bitmap image file format used in their products.
Most likely some old format without support. No further information could be found.
This xos 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.