Default DynamicVPN config on SRX100H2 does not allow remote access

We purchased an SRX100H2 about 3 years ago and it has been working well. We recently decided to enable remote access for a single user through its IPSec VPN feature. We factory reset the gateway and then went through the initial setup process but this time chose to have the remote access option enabled. We carefully read through all of the available documentation on the Juniper website and set the system up accordingly. The setup seemed to work without any issues. The remote user can use a web browser from home to go to the external IP address of the gateway and is presented with the Juniper login screen that accepts his credentials, allows him to log in and then allows him to download the Pulse VPN client. Unfortunately, when trying to log into the VPN with the Pulse client, the system seems to accept the user name and password (in that an incorrect username/password prompts re-entry) but then just hangs indefinitely and says that it is connecting. We've tried everything we can think of to fix this issue and have read through the relevant documentation on the Juniper website multiple times but we don't see any meaningful differences between our configuration and the suggested one for a dynamic VPN. We're stuck at this point and not sure what to do.  It seems like there's an issue with the IKE negotiation, but we can't see how to fix it.  Any assistance/suggestions would be greatly appreciated.

Details on the SRX100H2:

Please find the config attached.

Thanks for your time and help.