E4200 not keeping connection

Question

Hi
I bought a e4200 router about 3 weeks ago and after a power outage it decided it didnt like being connected to the internet anymore. So i got on the phone with cisco they determined the router was no good, mind you my laptop would connect wired. So they sent me a "refurbished" one, so i set it up. The new setup was wonky because it said the same message "Your connected to your router but..." then after trying to get the connection its self and failing it came up with "congratulations you are now connected to the internet". That lasted 3hrs and 45mins then died, so i went upstairs to power cycle it, it decided to connect with the old settings. That lased 25mins then died, so i reset it and reconfigured the router. Wouldnt connect, i checked my mac address and it was using my wireless one and kept turning on my wireless connection durring the install. So i cloned my wired mac address and got the internet for roughly an hour... then it died. So i reset it again and kept the wifi off got it going and decided to go to sleep. I wake up and its still working after 8hrs, i go down stairs with my tablet and i dies again. This time it refuses to reconnect, refuses to reset back up just doesnt want to work.
Heres my setup:
Time warner cable with Road runner
Motorola Surfboard (forgot model)
Linksys e4200 router ver. 1.0.3
ethernet wire run in cat6 with a total length of 285ft of wire from modem to wall connection (long story made short by saying isp's are ignorant)
Using either a macbook pro or toshiba satilite to connect to it
Now i can get fantasticly strong wired connection with a decent speed test score. I will be back on the phone with linksys again today.

Answer 1

1.  where is your router located? 
     Why I asked:  The router's location has a big impact on your router's wireless connectivity.  If there are a lot of obstructions between the router and the wireless devices (such as thick walls, metals and stuff) or other devices which also travel at 2.4 ghz which is interfering with your router's signal, it could cause your wireless signal to drop significantly. 
Also, since E4200 has been known to overheat, it is best to place your router where it gets enough ventilation and has a solid base to stand on. 
2.  What's your ISP?
     Why I asked:  because Cable, Static and DSL lines have different configurations.  the wrong configuration coud cause you not to go online or have intermittent signals. 
Check out these links for proper configuration based on ISP:
DSL ISP
Cable ISP
Static IP account
Also, try giving your ISP a call... maybe they also have problems with the internet connection on their end. 
3.  What is your security settings?
Why I asked:  Because switching to WEP wireless security can lower the network speed to Wireless-G mode.  choose WPA2. 
You could also do the following fixes:
1.  tweak around with the MTU
2.  Disable UPNP
3.  click this link.  It's got all the information you might be able to use
"Don't fix it if it ain't broken."