@Carl 

Thanks for replying. I did see the remote toggle switch but it would not allow me to move it to remote. That is when I would get the  "send error". I spent some time on the help line and we determined I should return the plugs. They don't know how the incorrect software was loaded on the plug but I was able to prove it to them. They started to take me through changing my router settings but I decided having paid as much fo the plugs as I did, I should have to correct a manufacturing issue.

@Chasm I have asked about this so many times because it happens with my smart bulb as well.  It worked for a full year then one day if would no longer allow me to turn the remote control option switch on.   One day out of the blue my Amazon echo just mentioned that it was now connected.  2 days later it wouldn't connect and would not allow me to turn the remote control option on.  The entire time giving me the "cloud send cmd failed" message.  Do a search for this and you'll see so many complaints about this yet not once has Kasa replies to me about this.