SCCM2012-Removing orphaned DP server from Primary Console and DB

Recently, we had two servers with DP roles, to be removed. But, I could not do a clean uninstall as they were already down.
I removed the DP role from the Console, but when trying to delete the server, I got this error:

 The server “\\<server_fqdn>” cannot be deleted because it contains the following site system roles:

Component server

I remember installing PXE role on it and then removing it.

Resolution:

1. Make sure all the roles apart from Component Server and Site System are removed.
2. On the Primary Server open regedit, go to

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SMS\Components\SMS_SITE_COMPONENT_MANAGER\Component Servers\OFFLINESERVERNAME

Under Components/each sub key there will be a value called Deinstallation Start Time.
This indicates how long server has been trying to reach the DP.
Change this to 1.
3. Stop and restart the SMS_SITE_COMPONENT_MANAGER service .

Again wait for some hours, and the Component server will be removed and you can delete the Server.

The server “\\<server_fqdn>” cannot be deleted because it contains the following site system roles:
Component server
- See more at: http://www.faqshop.com/wp/configmgr-2012-unable-remove-component-server-site-system-role#sthash.d2I35KS6.dpuf

The server “\\<server_fqdn>” cannot be deleted because it contains the following site system roles:
Component server
- See more at: http://www.faqshop.com/wp/configmgr-2012-unable-remove-component-server-site-system-role#sthash.d2I35KS6.dpuf

The server “\\<server_fqdn>” cannot be deleted because it contains the following site system roles:
Component server
- See more at: http://www.faqshop.com/wp/configmgr-2012-unable-remove-component-server-site-system-role#sthash.d2I35KS6.dpuf

The server “\\<server_fqdn>” cannot be deleted because it contains the following site system roles:
Component server
- See more at: http://www.faqshop.com/wp/configmgr-2012-unable-remove-component-server-site-system-role#sthash.d2I35KS6.dpuf