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When Firefox starts, window opens, "Is your PC slow" by Systweak. powered by Afterdownload cannot delete

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  • 6 have this problem
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  • Last reply by user633449

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Yesterday, when I turned on Firefox, an Ad for a Registry cleaner pop up on the opening page. I tried to delete the pop up but there is no "close" button. I tried to delete using Add or Remove Programs Control panel), did not show up in the Display list. Restarted, no change. Tried : System Restore, no effect still would not delete. If I opened a "New Window" it would be free of the Ad pop up. In desperation I tried to download the Registry cleaner, got an error message from my virus scanner that the .exe file was a possible virus. Ran my virus scanner (ESET) & DELETED THE .EXE FILE. Opened FireFox, the popup window was still there.

Yesterday, when I turned on Firefox, an Ad for a Registry cleaner pop up on the opening page. I tried to delete the pop up but there is no "close" button. I tried to delete using Add or Remove Programs Control panel), did not show up in the Display list. Restarted, no change. Tried : System Restore, no effect still would not delete. If I opened a "New Window" it would be free of the Ad pop up. In desperation I tried to download the Registry cleaner, got an error message from my virus scanner that the .exe file was a possible virus. Ran my virus scanner (ESET) & DELETED THE .EXE FILE. Opened FireFox, the popup window was still there.

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Try the Following:

Scan for Malware

Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try some of the following programs to scan for malware:

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Reset Firefox

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

  1. Go to Firefox > Help > Troubleshooting Information.
  2. Click the "Reset Firefox" button.
  3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
  4. Firefox will open with all factory defaults applied.


Further information can be found in the Refresh Firefox - reset add-ons and settings article.

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