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Can't log on to website after refresh, and reinstall

ccl1995
ccl1995
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Hello, i recently refreshed as well reinstalled my firefox and chrome browsers, since there was a redirection virus which leading to Yahoo.com repeatedly on certain websites. Now i can't log on to my university's website as it says it has Error code: sec_error_bad_signature, even though previously i could log on before i caught this virus and fixed it?? can you please help me solve this problem?

Hello, i recently refreshed as well reinstalled my firefox and chrome browsers, since there was a redirection virus which leading to Yahoo.com repeatedly on certain websites. Now i can't log on to my university's website as it says it has Error code: sec_error_bad_signature, even though previously i could log on before i caught this virus and fixed it?? can you please help me solve this problem?

All Replies (1)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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Is it just on one site or do you get that error on many sites?

The most common reason for getting "sec_error_bad_signature" on numerous sites seems to be the Avast Web Shield. Web Shield intercepts your browsing and filters it, but to filter secure sites, it presents "fake" certificates to Firefox. Avast should have set up Firefox to trust its fake certificates but that seems to fail on a regular basis.

To test this theory, try turning off scanning of encrypted sites. I saw these steps in another post:

  1. Open the Avast dashboard on the affected system.
  2. Select Settings from the left sidebar menu.
  3. Switch to Active Protection.
  4. Click on Customize next to Web Shield.
  5. Uncheck the "Enable HTTPS Scanning" option and click ok

If that resolves the issue, but you prefer to filter encrypted communications, you may need to import the Avast! signing certficate into Firefox's Certificate Manager, Authorities tab.