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Constantly getting SSL_ERROR_RX_UNKNOWN_ALERT when trying to access some sites and Youtube videos won't load

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Hello,

Just yesterday I started having issues on my computer with Firefox. I play Elite Dangerous and went to the forums to check a recent update, and instead it sends me to an error screen with the message: "SSL_ERROR_RX_UNKNOWN_ALERT."

Screenshots:

https://i.imgur.com/gwGHUxG.png

https://i.imgur.com/zLztR9u.png

I refreshed firefox, deleted cache data/cookiees, etc. I also uninstalled AdBlockerPlus thinking that was the problem. None of these solved the issue, and Firefox works fine on my home internet (same internet as this PC) on my Windows Surface Pro 3 tablet.

Thank You

Chosen solution

Hello,

Well the problem seems to have somehow resolved itself. The websites and Youtube are all working fine now.

Thank you for all your help although I still do not know what the issue was. I'm guessing something updated that corrected this error. I'm guessing it was something to do with security certificate authentication or something, I'm not sure.

Read this answer in context 👍 0

All Replies (12)

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Forgot to ask. Is this on many websites, some, a few?

Please provide public link(s) (no password) that we can check out. No Personal Information Please !

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Hello,

Yes it is on multiple websites. E.g.

https://www.winthrop.edu/

https://forums.frontier.co.uk/

I have Bitdefender, but this issue is confined to my main PC. Bitdefender doesn't cause issues on my tablet.

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I had no issue with those links.

Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?


Start your Computer in safe mode with network support. Then start Firefox. Try Safe websites. Is the problem still there?

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode Starting Any Computer In Safe Mode; Free Online Encyclopedia

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Neither of those worked.

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I called for more help.

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You can check the connection settings.

  • Options/Preferences -> General -> Network: Connection -> Settings

If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

See "Firefox connection settings":


Boot the computer in Windows Safe mode with network support to see if that has effect in case security software is causing problems.

Do a malware check with several malware scanning programs on the Windows computer.

Please scan with all programs because each program detects different malware. All these programs have free versions.

Make sure you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.


https://support.kaspersky.com/viruses/utility

See also:

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Hello,

Changing the proxy settings did nothing.

I already have Malwarebytes. I scanned with that and the other programs you suggested and my computer came up clean.

Could the drivers/software from another device be an issue? This started occurring after I got a new set of headphones on Friday. Steel Series Siberia 150, specifically.

Modified by flavivsaetivs

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For me this looks like an issue with software that acts like a man-in-the-middle and places itself in the connection chain. This can be security software or malware or the possible use of a proxy, so maybe check the network settings and try to reset the router (power off, wait at least 30 seconds before restarting).

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Chosen Solution

Hello,

Well the problem seems to have somehow resolved itself. The websites and Youtube are all working fine now.

Thank you for all your help although I still do not know what the issue was. I'm guessing something updated that corrected this error. I'm guessing it was something to do with security certificate authentication or something, I'm not sure.

Modified by flavivsaetivs

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Here's hoping. After a few days, if the problem is gone, Please flag your last post as Solved Problem so others will know.

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Will do, thanks for all your help. I'll be sure to ask again if it comes back and maybe pinpoint specifically what went wrong.