How to Bypass Windows 11's TPM Requirement Using Registry Hacks
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If you just have a regular Windows 11 install disk or ISO, you can bypass the Windows TPM and RAM requirements by making some registry changes during the install.  Note that this method only works on a clean install.

1. Boot off of your Windows 11 install disk.  
2. Hit SHIFT + F10 to launch the command prompt. 
3. Type regedit and hit Enter to launch registry editor.
4. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\Setup. 
5. Create a new registry key under Setup and name it LabConfig. To create a registry key, right click in the right window pane and select New->Key. Then enter the key name.
6. WIthin  LabConfig, create DWORDs values called BypassTPMCheck and BypassSecureBootCheck and set each to 1. To create a new DWORD value, right click in the right window and select new DWORD (32-bit) Value then name the key, double click to open it and set it to 1. 
   If you also want to bypass the RAM requirement, add a DWORD values for BypassRAMCheck.
   More:
     BypassCPUCheck
     BypassRAMCheck        -- I don't need it because I have 12GB RAM, > 8GB.
     BypassSecureBootCheck
     BypassStorageCheck
     BypassTPMCheck
7. Close regedit and the command prompt.

You should be able to continue with your Windows 11 installation as normal.

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Convert MBR to GPT by Reformatting the Drive
       ?GPT to MBR?

I got the following error:
"Windows cannot be installed to this disk. The selected disk is of the GPT partition style"

Solution:
Step 1. Turn off the PC and put in the Windows installation DVD or USB.

Step 2. Boot the PC from the DVD or USB.

Step 3. In Windows Setup, press "Shift + F10" to start Command Prompt.

Step 4. Enter the following command in order:

	diskpart
	list disk
	select disk # (# is the numeric id of the disk)  (in my case, it is: select disk 0)
	clean
	convert gpt 
	 or
	convert mbr (in my case, it is mbr!) 
	exit

Step 5. Close Command Prompt.

Step 6. Continue the Windows installation.

After the conversion, the drive will appear as a single area of unallocated space. Choose the unallocated space and click Next. Windows will begin the installation without sending the same error. 

https://www.easeus.com/partition-master/the-selected-disk-is-of-the-gpt-partition-style.html