Updating maps

May say that but once it starts downloading you'll probably find it's much quicker.  I updated maps yesterday and was told over two hours but it completed in under 30 minutes.  Leave it connected overnight just in case.

I rely on the watch to wake me up, so no chance of leaving it on the cable overnight. There's over 15GB of data to be downloaded. This process is ridiculous. 

Works for most of us, my map download was over 7Gb and as stated took around 30 minutes.  No map is 15Gb so no idea where you're getting that number from, if it's multiple maps just do one at a time.

It works for most because it has to. Apparently, there's no other way. Getting constant server communication error really doesn't help :( 

Well you haven't answered how you're needing to download 15Gb?  It certainly can't be one map.

If you're getting constant server communication errors something is wrong with your set up somewhere, I've only seen that message a few times in over 10 years, run through this FAQ https://support.garmin.com/en-US/?faq=uZQHyc3C4s2S0wfUYR2QY9&searchType=noProduct

Thank you for your replies, but you're the very opposite of helpful. I explained in the very first post that it's a new watch, so clearly all the maps on it need updating. 
I was able to update Edge 530 few months back no problem and nothing has changed about my setup since. Oh wait, I've put my monitor a bit higher, that might be it!

You still haven't answer the question, there is no map I know that's anywhere near 15Gb, so exactly what is causing your particular issue? Just because the Edge updated successfully is no reason not to follow the FAQ, for example I know Express has been updated a couple of times, the FAQ mentions ensuring it's up to date, is it?  Is anything else mentioned in the FAQ applicable?

I did not say there's a single map, I said maps, that's plural. I stated right in the first post that there's a whole bunch of them.

Nothing in FAQ was helpful. I did try uninstall, restart and install. Nothing. Disabling firewall did not help either. After a while it just started working so now I'm downloading one of the updates and I'll download the rest later this week.
  
I don't spend much time at home and when I am at home, I don't fancy eating up my bandwidth. The process is inconvenient for me. Would greatly prefer to download everything overnight and install in the morning. 

Well glad it's now working. Yes, I know you said maps hence me saying if it's multiple maps do one at a time, which it seems you're now doing.  Hopefully all will now go smoothly.

Well, it's going smoothly, but at 5MB/s, it's also going slowly. I was kinda hoping to be asleep by now :)