There has been a long (more that 10 year) history of the "Operation has timed out" error occuring with Sentinel updates, dating back to the first release of the Home Patrol 1. That particular error has almost always been observed by folks that are using Hughesnet satellite ISP. However, there have been other ISPs and situations from time to time that have resulted in that error... other satellite services, smaller local ISPs, wide area broadcast WiFi service in remote areas, or using a smartphone as a WiFi hot spot for the computer running Sentinel etc. Reports aren't too common from those situations, but not unheard of by any means.
The Sentinel "Operation has timed out" error historically indicates that Sentinel has reached Uniden's FTP server, and Sentinel has provided the correct login info (internally), but there is too long of a delay waiting for the FTP transfer to be initiated, or passed by the ISP. The users seeing that error have reported that they are able to reach the Uniden server at that time by pointing a browser to ftp://ftp.homepatrol.com and getting the login prompt returned from that server. You can't log in there without proper credentials (Sentinel handles that internally), but it shows conclusively that the user can reach the Uniden server and the server is responding.
If it was the Uniden site itself actually causing the "Operation has timed out" problem, there would be a large amount of users experiencing the "Operation has timed out" error at the same time, but it is reported as isolated instances, that were traced down to latency involved with the way Hughesnet handles FTP transfers... or other ISP situations noted above.
A ping check to ftp.homepatrol.com after a user is getting the "Operation has timed out error" will usually show the cause... the server is reached, but with excessively high roundtrip times and/or lost packets.
On the other hand, the Sentinel error message ending with "Remote server couldn't be reached" usually indicates that the path to the server is not able to be completed at all between the user and Uniden's server. If the Uniden server is actually down in that case, all users are affected and the large number of posts that are immediately seen on RR asking about it will reflect that very quickly. That message can also be an instance of just that user's FTP path (ports 20 & 21) being blocked on the user's end (modem, router or firewall), or the ISP itself purposely blocking FTP access. Users should check all settings in those devices, and/or call their ISP and request that FTP access be allowed for their service.... or at least confirmed that it is purposely being blocked for "security" reasons. This has been the case quite a few times with that error, rather than Uniden's server being down.
The "Remote server couldn't be reached" error can be narrowed down pretty quickly as well. If you can't reach the Uniden server log in page with the ftp://ftp.homepatrol address, but you can reach the Adobe ftp address as noted in post #40 above, most likely the Uniden server is actually down. If you can't reach either ftp address, it's most likely something on your end, or your ISP is blocking ftp access.
There are sometimes other Sentinel connection errors with other causes when trying to update, but not nearly as common as those 2.
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