The most common reasons  videos won't play on YouTube:

• The first method is to update the browser.-It's possible that the video won't play properly if your browser is outdated. As a result, make sure your browser is up to date. First, make sure your browser is up to date. Second, go online and look for the most recent version. You'll know if the browser is obsolete after comparing the two versions, and you'll know if you need to upgrade it.
• It's possible that too many caches and cookies are causing YouTube videos to stop performing. As a result, try to clear your cache and cookies. The instructions for clearing the cache and cookies vary depending on the browser you're using.
• Connection Settings Must Be Reset-It's possible that the issue stems from a lack of internet access. Resetting the connection settings is one solution to this problem. It might not completely solve the issue, but it's worth a go. A few mouse clicks are all that is required.. Access the Control Panel. Select Large Icons from the View menu and then Internet Options. Select the Advanced tab. Then press the Reset and Restore advanced settings buttons. Then, to implement the changes, click the Apply button.

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