Hi, and thank you for asking your question.
I'm afraid to inform you that a PXE-E61 error indicates a failed internal hard drive - its hardware components have gotten faulty and hence the drive is no longer functional; your system shows up this specific error because it's unable to detect the boot device it usually boots up from, that is, the failed hard drive.
There is simply no other solution to fix this issue, other than replacing the hard drive with a new one and reinstalling Windows. You may purchase a replacement hard drive from your local computer vendor or online from Amazon.
If you need to retrieve the data on the failed hard drive, you may look into purchasing an USB hard drive enclosure and using it to connect your failed drive as an external hard drive on your computer. If you need links to purchase the replacement drive and/or the enclosure, please reply back with your laptop model and I'll look up some resources for you to purchase them from.
I'm sorry I could not be of further help with this, but our hands are indeed tied in this case. If you need further assistance with this issue, please reply back using the box below. I'd appreciate it if you could kindly take a moment to submit a positive rating at the top of this page. Thank you :)