Large file uploads fail 100% of the time

@XfinityEva​ There is nothing to try on our end. I'm a Cisco engineer, I know routing very very well. This is a routing issue on your end, but nobody at Xfinity is willing to change my routing to fix it. MetroNet just pushed Fiber right through my back yard, so you've got about 2 weeks to fix it. My entire neighborhood is ready to walk away from Xfinity forever. 

I do apologize for the inconvience this security error is causing you. This is a security error that we rarely see. There are several possible reasons that can cause the ERR_SSL_BAD_RECORD_MAC_ALERT error. Some common causes are:

1. An outdated version of the Google Chrome browser
2. An outdated version of your Operating System
3. A problematic antivirus or firewall program that intercepts the SSL traffic
4. A problematic network adapter or Killer Network Card
5. A router configuration that is not set correctly, such as MTU (maximum transmission unit) size.

@XfinityRichard​ That's a nope to the first 4, and Xfinity users don't have access to that side of your hardware to set the MTU to 1400, yet even though I've requested this from support via a phone call, it never happened.

Again, works flawlessly when hotspotting (AT&T), When using CenturyLink (neighbors wifi), or using Starlink (my backup). I also have a friend across town that just left Xfinity for MetroNet, so I went over to his place on Sunday with my laptop to test. Flawless (and blazing fast). MetroNet doesn't light the fiber in my neighborhood for another 2ish weeks sadly. 

@XfinityAmandaB​ I have zero uncorrectable errors on my end, signal strength is good, signal power is good. The one similarity is that this all started after Xfinity emailed me and told me I had to replace the modem/router as the one I was running out being phased out. I have been on the phone with xfinity support a few times where they have made changes to the router but that didn't fix anything. 

@EG​ Given my admonishment of Xfinity and their practices, in addition to what they will see as me promoting a direct competitor (even though I gave fair warning the clock was ticking), I have little doubt this entire thread will be deleted by someone at Xfinity. I have, however, taken screenshots should that happen and that will be Act II of my story on why to avoid Xfinity. ;) 

Hi there @user_7pur39. I am sorry to hear that you are having troubles with you Internet service. You are in the right place and we are happy to assist you. 

Please send us a direct chat message with your full name and complete service address to “Xfinity Support”. To do so, click on the chat icon located at the top right of this forums page.
Here's the detailed steps to direct message us: 
 • Click "Sign In" if necessary
 • Click the "Direct Message” icon (upper right corner of this page)
 • Click the "New message" (pencil and paper) icon
 • Type "Xfinity Support" in the to line and select "Xfinity Support" from the drop-down list
 • Type your message in the text area near the bottom of the window
 • Press Enter to send your message

Let me know if you have any questions.