Error 775 indicates that your receiver has lost contact with the dish. It's a purely on site error and the cause is within your particular installation. Usually a loose or faulty coax connection, a bad power inserter or a bad dish. Make sure the power inserter is plugged into a solid receptacle and not into a smart power strip. You can carefully check all of the coax connections making sure they are tight. If you don't find anything then a tech visit is likely in order.
I have experienced this for the second time in a month. This time it's going to take until next friday to get a technician here. So 6 days with no TV and they have the nerve to give me a $7.50 credit. A complete insult. Last time the technician came, he unplugged then re-plugged the SWIM and it worked. When I was on the phone with DirecTV, I did this at least ten times. And NO it was NOT plugged in to a surge protector. The end of my DirecTV contract cannot come soon enough.
When the tech came out, would you say he checked your whole installation? Or did he just go right to the SWM PI and do his little trick? Ask the next guy to please go over it top to bottom.
If you're getting 775 there's an interruption somewhere (obviously) and it's intermittent.
Are all the boxes out, or just one?
Usual causes are poorly made or burned connectors, connectors not tightened, low frequency barrels. After that I would make sure your signal is NOT passing through your SWM PI - I don't trust them. I prefer to let my PI simply power the system (maybe pass the signal to a minor box, but not the main HDDVR.)
Still having trouble? Replace your drop, and maybe the cable to that IRD. After that your LNB and splitter.
I really appreciate the time and effort you put into this post, but it’s too technical for me. I think the previous tech did check out the whole lot and found it all OK. I wouldn’t know how to begin doing the stuff you mentioned below, that’s how tech-dumb I am. It’s why I use a Mac—easiest computer to use, hands-down. Thank you again.