if you was able to get into your router once, I'm sure it is not bricked.
Everything sounds like a misunderstood setup of
1. Router's IP configuration
2. PC's IP Configuration
3. Wrong wired connection to the router.
Can you please simple sum up the following configuration:
1. What IPs is your home-network using?
2. What IP did you set on the network config of your M3420 ?
After this, I can maybe give you some hints
Everything sounds like a misunderstood setup of
1. Router's IP configuration
2. PC's IP Configuration
3. Wrong wired connection to the router.
Can you please simple sum up the following configuration:
1. What IPs is your home-network using?
2. What IP did you set on the network config of your M3420 ?
After this, I can maybe give you some hints
