An sdpkey file extension is related to the Spyware Process Detector and used for its data files.
SPDKEY file extension - Spyware Process Detector data
What is spdkey file? How to open spdkey files?
File type specification:
The spdkey file extension is associated with the Spyware Process Detector, an anti spyware software for Microsoft Windows operating system.
The spdkey file contains some kind of data.
Most likely some old format without support. No further information could be found.
This spdkey 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.