New hard drive, won't boot, light blinks

[Rikkilyn326]

Help! My desktop HP 24 All in One computer crashed so I replaced the hard drive. Now the light just flashes but the screen is black. My computer is only 15 months old and rarely used. I'd like to save it if possible. 

[TheOldMan]

I do not see in the post any mention of reinstalling Windows or any other software, so that might be the reason nothing is working.

There are several ways to get the needed tools to get going again.  First you will need a complete model number, then use the HP Cloud Recovery Tool to get the needed software, which you will need a working PC to accomplish.

https://support.hp.com/us-en/document/c06162205

If you wish to just do a Windows install and add drivers, etc after completion, then you can use the Microsoft tool

If you need the install media for Windows 10, you can make it from this Microsoft download

https://www.microsoft.com/en-us/software-download/windows10

With a working PC, scroll down to the "Using the tool to create installation media"
and then follow the directions. You can make either the DVD or USB.
When the install asks for the product key, click the I don't have a product key option to continue,
then the install will continue It will be activated once it connects to the internet, as it uses a digital key.

[Rikkilyn326]

How do I install anything if I'm just getting a black screen? I installed a new hard drive because I was getting the  "NO boot disk detected" error message and diagnostics indicated that a partition was damaged. 

What do I do now? I can't afford a new computer. 

[TheOldMan]

You will need a working PC to do the things listed which you will need a working PC to accomplish.  So in other words go to a friends house or a library if you do not have a working PC.  This link is for the HP Cloud Recovery Tool, which you must have the complete model number to get the correct software.

https://support.hp.com/us-en/document/c06162205

If you wish to just do a Windows install and add drivers, etc after completion, then you can use the Microsoft tool

If you need the install media for Windows 10, you can make it from this Microsoft download

https://www.microsoft.com/en-us/software-download/windows10

With a working PC, scroll down to the "Using the tool to create installation media"
and then follow the directions. You can make either the DVD or USB.
When the install asks for the product key, click the I don't have a product key option to continue,
then the install will continue It will be activated once it connects to the internet, as it uses a digital key.

Use this new media to install the Windows OS.  Boot the problem PC to this new media to install softwares.

[i386]

@Rikkilyn326

Does the old drive work? Is it completely dead? If it's 15 months old is it under warranty? If you know what you are doing and still have the old drive you may be able to clone the old drive to the new IF it's not too far gone.

You can get Macirum Reflect or Acronis True Image. Did you replace with a SSD? SSD drives are much faster that traditional drives. Most drives also come with cloning software.