How to mount boot-disk automatically after the computer restarts

Hello!
I am using RAM Disk 4.0.5 64-bit (trial) on Windows Server 2012 R2. I want to move TEMP_DB of SQL Server to this disk.

To test how it works, I did the following:

1. Connected to the server via RDP and created a boot-disk with the following parameters: Size 4096 MB; Drive Letter M:; Hard Disk Emulation checked; File System NTFS.
2. Mounted the created disk.
3. Restarted the computer and connected to it via RDP. And I did not find the disk.
4. Run the RAM Disk control program and saw that the disk was not mounted: there was a red cross icon next to the disk M in the 'Disks mounted on boot' list.

How can I make the disk mount automatically when the computer starts, so that the SQL Server service can use it right away?

It is supposed to mount automatically and remember its last mount state. In other words, if you restarted with the disk M:\ mounted, it should be automatically remounted at next boot; and if you restarted with the disk unmounted, it will not be mounted automatically.

Unfortunately I can't tell what is the exact reason of not mounting in your case, but please try the following:

1. Try a different drive letter other than M:\
2. Try with the Hard Disk Emulation option unticked.
3. Try disabling hybrid boot as described below.

To disable the hybrid boot, open an elevated command prompt and type

REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Power" /V HiberbootEnabled /T REG_DWORD /D 0 /F

Alternatively, if you don't hibernate the server and want to save a few GBs of disk space, you can disable hibernation. This will permanently deactivate the hybrid boot as well. For that, in an elevated command prompt type

powercfg /h off