I wanted to share this experience with all. I eventually fixed it, as explained in below own-answer.

Lately, I noticed that some operations on my Windows 7 box were becoming slower and slower as days go by. I specifically faced this:

  • after having started a Java Web Start application (JWS): clicking some part of the GUI led to a delay before having the expected result.
  • after having started an application from a remote Linux box, using X11 forwarding, thanks to an X server for Windows: as with JWS, actions were delayed. BTW, I faced it with different X servers for Windows, so the X server itself didn't seem to be in cause.
  • upon launching an elevated operation: e.g. starting any application as Administrator. In that case, I faced a delay when the UAC window was displayed, with the message "Looking for credential tiles" lasting for a while.

In all above cases, I faced no actual delay just after having rebooted Windows, then the delay was increasing as days were going by. After 3 or 4 days, JWS or X11 forwarded apps were simply no longer usable due to delays above the minute. Similarly, after a few days, starting an elevated operation needed to wait for several minutes with the message ""Looking for credential tiles" until local Administrator account was proposed!

I investigated repeatedly to figure out what was causing such behaviors, knowing that it started once in the recent past (i.e. I wasn't facing this before):

  • First, I thought about some malware: but my installed AV, Avast Free Antivirus, didn't find anything.
  • Then I inventoried running services, stopped some, based on "personal suspicion" or based on what they were expecting to do. But no luck either.
  • Did the same with installed apps: even uninstalled most of them. Still no luck.

So, I had to work with this "pain" for quite a while, rebooting when it was becoming too unbearable.


I finally pinpointed the culprit: Avast Free Antivirus! Indeed, after fully disabling it, I no longer experienced any delay.

Before deciding to switch to another AV, I chose to determine if that was due to some specific option that I would have enabled a while ago and that induced the increasing delay issue. The other possibility was that an avast update introduced some bug that led to this.

And I figured out that it was due to "Settings-Troubleshooting-Enable anti-rootkit monitor" option: once disabled, I no longer faced any delay for the 2 first cases.
But, unfortunately, this doesn't solve the third case (UAC), contrary to what I once thought. This one has another source that I still have to discover...

BTW, to test, I used to start xeyeson a remote Linux box:

  • with above option enabled, the eyes were displayed after a few seconds,
  • when disabled: the eyes were immediately displayed, without any delay.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.