Update TROUBLESHOOTING.md

TROUBLESHOOTING.md

@@ -1,14 +1,27 @@
 ## **Troubleshoot your troubles**
 ### Where is the log?
-The logs are stored in /var/log/libvirt/qemu/vm_name.log, where vm_name is the name of the VM you're trying to boot. \
+The logs are stored in ***/var/log/libvirt/qemu/vm_name.log***, where vm_name is the name of the VM you're trying to boot. \
 By reading the few lines at the bottom of the log file, you get general idea of what might be an issue.
 
-### warning: host doesn't support requested feature, what is this?
+### **warning: host doesn't support requested feature, what is this?**
 This warning usually means that the feature guest is requesting is not available on host. \
 After the warning message, on same line, you'll see something like MSR(490H).vmx-entry-load-perf-global-ctrl \
-That's the feature it's missing, but I have no idea what most of them indicate. \
-If you've set Firmware for VM to BIOS, change to UEFI. \
+That's the feature it's missing, but I have no idea what most of them indicate.
+
+#### How to fix it?
+Make sure you've enabled ***Intel VT-d*** or ***AMD-Vi*** in BIOS Settings. \
+If you've set ***BIOS*** as Firmware for Guest, change to ***UEFI***. \
 In the cpu section in log file, you might see something like this: \
-***-cpu Skylake,vme=on,ss=on,vmx=on,...*** \
-Make sure you've set ***host-passthrough*** CPU model which'll produce ***-cpu host,...*** instead. \
-If it doesn't, I don't have any other ideas.
+***-cpu Skylake,vme=on,ss=on,vmx=on,...***. Although, it works in most cases, it doesn't in some. \
+Make sure you've set ***host-passthrough*** CPU model which'll produce ***-cpu host,...*** instead.
+
+### **shutting down, reason=failed, but no actual error?**
+If the VM fails without an error, SSH into your host machine, and run libvirt start script from SSH Client. \
+If the script works without producing error, you'd get blank screen, and you can try starting VM from SSH Client. \
+Both commands should be run as superuser.
+```sh
+sh /etc/libvirt/hooks/qemu.d/win10/prepare/begin/start.sh
+virsh start win10
+```
+
+If your troubles aren't done yet, I don't have any other ideas.