[SOLVED] - Web Setup Wizard/Component Manager Not Working - Magento 2

The first thing you need to do when you are unable to access your Component Manager page in your Magento 2x installation is to press F12, Click on Console & view the error message displayed there. Please look at the image below:

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The message displayed in red are the error messages(s). With this error message in hand you will begin to get some idea about the direction you need to take to troubleshoot.

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In my case, I copied the link that was causing the Error & tried to view it in the browser. When I did that I got new error messages generated as below:

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This was the error I was getting precisely:

[RuntimeException]                                                                                                                                                                                                      
  Failed to execute git clone --mirror 'git@github.com:rusdragos/m2-weltpixel-backend.git' '/var/www/html/var/composer_home/cache/vcs/git-github.com-rusdragos-m2-weltpixel-backend.git/'  
                                                                                                                                                        

I checked the 'composer.json' file in the Magento root directory and found the above git command and simply removed it. & voila!, my problem got solved.