Well you'd have to look for rejected blocks in your bitcoin debug.log
Would that be these?
Code:
warning='20 of last 100 blocks have unexpected version'
The expected block version at the moment is 0x20000002
I've seen messages saying
"invalid block=" and "is marked invalid"
a bit over a week ago for a block with the hash "0000000000000000013ee4a86822d37a061732e04ee5f41fb77168f193363d1b" at 477115
So I'm guessing the message might be similar - but I'm not sure and have never checked the code to see what other such messages there are.
One simple way on linux to see all block messages other than the standard expected ones is:
grep 000000000 debug.log | grep -v "new best="