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The C: drive on my Windows 8 machine is clicking away at 1 second intervals, writing to wfpdiag.etl. I'd like to find out why.

Looking at the Resource Monitor and the Sysinternals Process Explorer, I see that it's PID 4, "System" that is doing the disk access. It's writing about 32K (1 write) every second.

Here is the constant disk access:

And here is the periodic writing.

The "Writes" number increments once a second. Performance Monitor tells me it's writing to a file called wpdiag.etl, which I understand to be related to the Windows Firewall. Is there any way I can disable the writing to this file?

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The fact that System is doing what you say, is pretty normal. The fact that your drive is audibly clicking is not (presuming it's actually a louder than normal clicking. :) ). Have you checked the disk for defects using the manufacturer's utilities yet? – Ƭᴇcʜιᴇ007 Jan 20 '13 at 18:19
It is not a faulty hard drive. It is a file being written to. I'd like to get rid of the writing to the file. – pom Jan 20 '13 at 18:34
same problem, it's very annoying. btw how did you know exact file name? (wfpdiag.etl) I couldn't find where to look at... – Sarge Borsch Apr 15 '14 at 16:13
i have no such file, but my System process is constantly writing something – Sarge Borsch Apr 15 '14 at 16:29

Do you have software called Windows7FirewallControl from Sphinx? Software site:

Some have reported that it was responsible for this write pattern: Uninstalling or disabling it stopped the constant write activity to that file.

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No, I haven't installed any firewall or other network analysis or antivirus programs. This is basically a new Windows 8 install. – pom Jan 20 '13 at 19:26

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