First time IPXEAnywhere boot client displays a timeout and then goes into retry mode
The PowerShell script must generate the BCD files on the fly. In some cases this file creation may take too long which can cause a time out. This is typically seen in a configuration where you are not using an HTTP server and have the iPXE Boot Loaders enabled.
Depending on how many image BCD files are being returned it can take a retry or two before the machine is prompted with a menu or will boot to an image.
The second attempt does not go into retry mode as the BCD files, once created will be reused.
This will usually be seen as an issue in a lab situation during testing as stopping and starting the service causes the temporary files to be deleted and these must then be regenerated each time.
Ensure that the HTTP service is enabled in the configuration file.