splwow64.exe

Windows ProcessMicrosoft Corporation

Also called splwow64, spooler wow64, 32-bit print thunk

WindowsSystem Component

Print driver host for 32-bit applications on 64-bit Windows. It is the thunk that lets a 32-bit app talk to 64-bit print drivers. spoolsv.exe is the Print Spooler.

What you need to know

splwow64 is the 32-bit print thunk, not the spooler.

splwow64.exe exists so a 32-bit program can print on 64-bit Windows. The Print Spooler service still lives in spoolsv.exe. PrintIsolationHost.exe isolates drivers. Ending the thunk does not empty the queue folder.

Safe?: Yes, on 64-bit Windows
Is it the spooler?: No. spoolsv is the spooler
Why is it here?: A 32-bit app printed

Feex says

If splwow64 stays after I closed a 32-bit Office, I check whether that app still holds the printer. I do not restart the whole spooler as my first click unless jobs are stuck in spoolsv.

What is splwow64.exe?

splwow64.exe is the 32-bit print thunk on 64-bit Windows. A 32-bit app cannot load a 64-bit print driver directly, so this host bridges it. It is not spoolsv.exe, the Print Spooler process.

What does it do?

It translates print calls from 32-bit apps. The queue, port monitors, and service still belong to spoolsv.exe. Isolation of a bad driver is PrintIsolationHost.exe.

Why is it running?

A 32-bit Word, browser, or CAD program printed or opened printer properties. The thunk can linger for a while after the last 32-bit print. A 64-bit-only PC that never prints from 32-bit apps may rarely show it.

Is it safe?

Usually safe

System32 splwow64.exe is the Microsoft thunk. A splwow64.exe in a "printer crack" folder is not. This file is still not the spooler.

A legitimate copy normally runs from:

C:\Windows\System32\splwow64.exe

64-bit Windows only
Triggered by 32-bit print clients
Spooler process: spoolsv.exe

Can I end it?

That 32-bit print session dies

Ending splwow64.exe drops the thunk. Jobs already in the spooler stay in spoolsv.exe. Clear PRINTERS only after you stop the Spooler service, not by ending this host alone.

Can I remove it?

Do not delete splwow64.exe. 32-bit apps would fail to print. Disable the Print Spooler only if you accept no local printing. That decision is about spoolsv, not this thunk.

Should it start with Windows?

A 32-bit print starts it. It is not a Startup Apps checkbox.

Normal resource behavior

These are contextual labels, not universal averages.

CPU: Rises while a 32-bit app renders a job
Memory: Can linger after the last print. Microsoft documents a timeout
Disk: Low here. Spool files belong to the spooler
Network: Follows the printer the 32-bit app used

File information

splwow64.exe file information
Executable name	splwow64.exe
Common legitimate path	C:\Windows\System32\splwow64.exe
Publisher	Microsoft Corporation
Signature expectation	Signed by Microsoft Windows

Common problems

Thunk never exits

A 32-bit app still has a printer DC open. Close that app. If the queue is wedged, that is spoolsv and the PRINTERS folder.

People disable Spooler to stop splwow64

That also kills 64-bit printing. End the 32-bit client first.

Troubleshooting

Diagnose before you change anything destructive.

Name the 32-bit app that printed

Task Manager command line and the last program that showed a print dialog. 64-bit Notepad does not need this thunk.

Stuck jobs: treat spoolsv, not the thunk

Stop Spooler, clear System32\spool\PRINTERS, start Spooler. Ending only splwow64 leaves the queue files.

Technical details

splwow64.exe technical details
Image name	splwow64.exe
Role	32-bit print driver thunk on 64-bit Windows

Sources and verification

Reviewed by Feex editorial. Last verified August 2026 Status: Feex Reviewed. How we research.

Microsoft Learn: Print Spooler · spoolsv hosts the spooler service
Microsoft Support: printer problems · Stuck jobs live in the spooler, not the thunk
Foxhole process map · First-party samples on Windows PCs. Not a lab benchmark.

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