When you try to deploy new machine via PXE using SCCM Task Sequence, you may get the following error message:
Pending Request ID : 18

This error can be solved by clearing the required PXE deployment flag. Right-click on the machine in the SCCM console, and then select “Clear Required PXE Deployments“:

A new window will appear and select the deployment to clear the flag.

Then, you can now restart the machine and boot once again via PXE. The deployment will start as expected on your SCCM TS.
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