Hopefully I am not hijacking this thread with my experiences, but this thread caught my eye since I think I had the same error and found a workaround.
I have a 99i running 3.3.10. I was replacing 2 2476D with 2 2477D units. These are in the same switch box and on the same circuit. No known communication issues with the 2476Ds. I added my first 2477D (23 C6 D9) in the ISY with no problems. When I went to add the second 2477D (23 BF 5), it failed with an error about the query Insteon engine. I got this error multiple times. I had never seen this error before. I knew the 2477D was powered up and functioning. I went to add the 2477D a third time, but this time I told the ISY that it was a 2477D instead of letting it "auto discover" like I had always done. This time it worked fine. My partial log is attached, I am not sure why I didn't catch the rest of the activity. I had no trouble using the ISY replace feature, once I got past the adding issues.
ISY-Events-Log.v3.3.10__Sat 2013.07.06 10.22.12 AM.txt