Does the BIOS/UEFI settings show the new memory properly? If there are any configurable memory settings in the BIOS/UEFI settings, then make sure they are set to auto.
In the BIOS/UEFI settings, turn on the extended POST as it will perform a very simple memory check during POST.
Is your system firmware up to date?
While booted into Windows, check Event Viewer to look for the error from the time it was rebooting. I'm guessing it will be a kernel panic. You may get some information about what is happening from the recorded error.
When Windows fails to boot and you are presented with the advanced boot menu, there may be a diagnostic option which may include a Windows built-in memory test. Also try booting into Safe Mode from the Windows advanced boot menu (also accessible by pressing F8 just before Windows starts to load). If this works, then you likely have a driver issue. You can also enable Boot Logging to see where things went wrong. You could also try running Memtest86 or Memtest86+ to see if any errors show up (try with just the original memory as well to make sure these tests are compatible with your laptop). Also make sure the laptop is unplugged and the battery is removed before installing or removing memory.
While you may have received an incorrect, or incompatible or a defective module, it is also possible you are now finding out your laptop has a latent flaw which is revealed by the larger memory module.
I suggest you contact Crucial Support directly as they are very pleasant to deal with and they can verify you received the correct part for your laptop and they may offer to exchange it.
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