Hello @mayanksandee,
I am sorry about the issue you are having with installing and activating W3 Total Cache.
There is a couple of things that you can try to help us figure out what might be causing this.
Make a backup of your .htaccess file and replace it with the default one.
Make sure you are not using any other caching plugin or server-side caching as multiple levels of caching may cause conflict.
Also please contact your host and check if 000webhost supports W3 Total Cache.
I hope this helps, and please let us know if you have any other questions.
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