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Error message recieved when applying TLS/SSL

  • 5 replies
  • 2 have this problem
  • 1 view
  • Last reply by cor-el

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When I am trying to update my Mozilla.cfg and add preferences I receive the attached error message when I apply the following settings:

LockPref("security.enable_tls", true);

LockPref("security.enable_ssl2", false)

LockPref("security.enable_ssl3", false);

lockPref("security.tls.version.min", "2");

lockPref("security.tls.version.max", "3");


in addition to the issues with adding TLS, SSL, and TSL min/max version, I also received the same error message when I try to apply the following lines:

lockPref("browser.history_expire_days_min", "40");

lockPref("browser.history_expire_days_min", "40");


Running the most current version of Firefox (at the time I created this post) 61.0.1


Error message in case the attachment doesn't work:

Netscape.cfg/AutoConfig failed. Please contact your system administrator.

Error: defaultPref failed: [Exception... "Component returned failure code: 0x8000ffff (NS_ERROR_UNEXPECTED) [nsIPrefBranch.setStringPref]"  nsresult: "0x8000ffff (NS_ERROR_UNEXPECTED)"  location: "JS frame :: prefcalls.js :: defaultPref :: line 53"  data: no]
When I am trying to update my Mozilla.cfg and add preferences I receive the attached error message when I apply the following settings: LockPref("security.enable_tls", true); LockPref("security.enable_ssl2", false) LockPref("security.enable_ssl3", false); lockPref("security.tls.version.min", "2"); lockPref("security.tls.version.max", "3"); in addition to the issues with adding TLS, SSL, and TSL min/max version, I also received the same error message when I try to apply the following lines: lockPref("browser.history_expire_days_min", "40"); lockPref("browser.history_expire_days_min", "40"); Running the most current version of Firefox (at the time I created this post) 61.0.1 Error message in case the attachment doesn't work: Netscape.cfg/AutoConfig failed. Please contact your system administrator. Error: defaultPref failed: [Exception... "Component returned failure code: 0x8000ffff (NS_ERROR_UNEXPECTED) [nsIPrefBranch.setStringPref]" nsresult: "0x8000ffff (NS_ERROR_UNEXPECTED)" location: "JS frame :: prefcalls.js :: defaultPref :: line 53" data: no]
Attached screenshots

Modified by chwest90

Chosen solution

hi, don't put quotation marks around integer values. in addition you can leave out the browser.history_expire_days_min preference, it is outdated and won't have any effect...

edit: also it's "lockPref" - you'll have to be careful with capitalization in this file

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All Replies (5)

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Chosen Solution

hi, don't put quotation marks around integer values. in addition you can leave out the browser.history_expire_days_min preference, it is outdated and won't have any effect...

edit: also it's "lockPref" - you'll have to be careful with capitalization in this file

Modified by philipp

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Great, thanks Philipp that worked for the min/max version, but what about the "enable_tls", "enable_ssl2", and "enable_ssl3" ?

edit reply: I do have all my lines set to "lockPref" it appears my web browser helped itself to some auto-capitalization.

Modified by chwest90

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i think those prefs are outdated and won't do anything in modern firefox versions either. you'll already achieve your goal by setting

lockPref("security.tls.version.min", 2);
lockPref("security.tls.version.max", 3);
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is there any way to still set it using Mozilla.cfg? I have very specific instructions to apply these settings. If not, I can simply submit for an exception, but I would still like to try make it work.

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SSL2 support was removed in Firefox 8.

SSL3 support was removed in Firefox 39.

These prefs are no longer supported since Firefox 23.

lockPref("security.enable_tls", true);
lockPref("security.enable_ssl2", false)
lockPref("security.enable_ssl3", false);

Bug 733642 - Allow the user to enable any version of TLS that libssl supports, maintaining our current defaults [23]

#733642#c1: This patch drops support for the security.enable_tls and security.enable_ssl3 prefs with new prefs security.tls.version.min and security.tls.version.max.