This article explains how to enable SSL 3.0 support on Firefox using Windows and macOS, but also on Chrome, Edge, and Internet Explorer using Windows. SSL 3.0 is already active on Safari for macOS and cannot be disabled.
Steps
Method 1 of 3: Firefox for Windows and macOS
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Step 1. Open Firefox on your PC or Mac
It is usually found in the "All Programs" section of the Start menu (Windows) or in the "Applications" folder (macOS).
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Step 2. Type about: config in the address bar and press Enter
A warning message will appear.
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Step 3. Click on I accept the risk
It is a blue button located in the center of the page.
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Step 4. Type tls in the search bar, which is large and located at the top of the screen
The list of options below will be filtered to show only relevant results.
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Step 5. Double click on security.tls.version.max
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Step 6. Enter 0 as an integer
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Step 7. Click Ok
SSL 3.0 support will then be activated on Firefox.
Method 2 of 3: Chrome for Windows
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Step 1. Open Chrome on your PC
It is usually found in the "All Programs" section of the Start menu.
This method only works on PC
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Step 2. Click on ⁝
It is located at the top right.
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Step 3. Click on Settings
It's almost at the bottom of the menu.
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Step 4. Scroll down and click on Open proxy settings
A window titled "Properties: internet" will appear.
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Step 5. Click on the Advanced tab
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Step 6. Scroll down and check the box next to "Use SSL 3.0"
It's almost at the bottom of the list.
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Step 7. Click Ok
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Step 8. Restart your PC when prompted
Restarted Windows, SSL 3.0 will be supported on Chrome.
Method 3 of 3: Microsoft Edge and Internet Explorer for Windows
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Step 1. Press ⊞ Win + S
The search bar will open.
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Step 2. Type internet options
A list of relevant results will appear.
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Step 3. Click on Internet Options
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Step 4. Click on the Advanced tab
A list with various checkboxes will appear under the heading "Settings".
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Step 5. Scroll down and check the box next to "SSL 3.0"
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Step 6. Click Apply
It is located at the bottom of the window.
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Step 7. Click Ok
It is located next to the "Apply" button.
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Step 8. Restart your PC when prompted
After restarting Windows, both Edge and Internet Explorer will support SSL 3.0.