Unable to start automatically from the SSD, but it works when you connect it manually.
Unable to start automatically from the SSD, but it works when you connect it manually.
And as mentioned, after the initial boot from clone, it's best to start without the HDD connected. Try launching with just the SSD. Even though the clone was successful, the settings or BIOS might be incorrect. I've noticed once with ASRock BIOS that the system refuses to boot from the second drive after the first was installed. Removing the UEFI settings and partitioning the HDD should resolve the issue—leaving only one drive with bootable partitions. You can use MiniTool Partition Wizard for this task.
Your suggestions appeared effective! You rerouted the SATA cable to a different motherboard slot and then installed the SSD in its correct position, which now lets Windows identify it as Drive 0. Thanks for your help—I’ve been having trouble all day, but it seems resolved now.