Ok, it looks like I've managed to resolve the issues with my Wi-Fi.
Whilst playing around trying to get my Wi-Fi to work I went into Preferences - Advanced Network Configuration and double clicked on Wireless Network to bring up the settings box. On checking the settings once again I noticed that the BAND as set to Automatic. When I clicked on this box I saw two settings for 5ghz and 2.4ghz. Instead of leaving the setting on automatic I changed it to 5ghz to see what would happen as my laptop etc were running on 5ghz. Having changed the setting to 5ghz I shut my RPI down and disconnected the Ethernet cable. When I booted up my RPI I saw that the wireless Wi-Fi was working. I could see it on my phone app, see below image and when I opened up the app it showed me that my RPI was connected wirelessly to the internet at 5Ghz and it gave me the IP address. On entering this IP address into IE I was able to see Astroberry Server and connect to it.
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I have tried this a few times with the RPI in different places around my house and I am able to connect to the internet. I don't know why but in my app it sometimes shows that I'm connected at 5 ghz and other times at 2.4ghz even though the settings in Astroberry Server are set to 5GHz.
For some reason it would appear that my router does not like the automatic Wi-Fi settings in Astroberry server and you have to select either 5ghz or 2.4ghz. This may help anyone else who is having a similar problem or it may just be unique to my set-up and router.
I also ran the script to check my network configuration and my wireless network showed up
Image showing Wi-Fi before RPI booted up
Image showing Wi-Fi after booting up and changing the settings
THANKS FOR ALL THE HELP AND ADVICE WITH THIS ONE.
I'm now going to move onto setting up my profile in Astroberry Indi Web Manager, with regards to this I use an Altair GP Cam on my guider which will be used by PHD2. Do I need to set this up in the Indi Web Manager or leave it out so it can be used by PHD2.
Thanks
Doug