Guys ! yesterday I faced this problem. I had installed 4GB of RAM and my computer showed 2.64 GB usable

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And I found found videos and they told that msconfig will solve this problem.

But for me msconfig had not worked So I just tried this method

I went to System Settings and just under advance system settings > performance > settings > advanced > virtual memory > I unchecked ' automatically manage paging file size for all drives ' and after that I set that to no paging file.

And when I restarted my pc then there was unusual behaviour so I again checked ' automatically manage paging file size for all drives' then after restart My windows started using my RAM

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So Finally I solved my problem ! If any one of you more know about this topic can you tell me how did it happened ! What happened behind the process

And it's for those too who are not getting results using msconfig. You may try this it may work for you !

Thanks