What Is a .PNF File?
You found .pnf files in a Windows folder and wonder what they are. They are precompiled driver-setup files Windows makes on its own. Here is what they do and whether to touch them.
What a PNF file is
A .pnf file is a Precompiled INF — a binary, ready-to-use version of a driver's text .inf setup script. Windows compiles each .inf into a .pnf the first time it processes a driver so future installs and Plug-and-Play checks are faster. They live in C:\Windows\INF and in driver store folders.
Where they come from
Windows creates them automatically — you never make one yourself. Every installed driver typically has a matching .inf and .pnf pair.
Is it safe to delete?
Technically yes — Windows will simply regenerate a .pnf from its .inf the next time it needs it. But there is no benefit: they are tiny and deleting them only slows the next driver operation slightly. Leave them alone. Do not open or edit them; they are machine-generated binary and useless to read.
FAQ
Can I open a .pnf file?
No usefully — it is compiled binary driver data, not text. Leave it to Windows.
Can I delete .pnf files?
Yes, Windows regenerates them, but there is no reason to. They are tiny and harmless.
What creates .pnf files?
Windows itself, by precompiling each driver's .inf file for faster installs.