This could be related: I had a similar issue with access with my ssh client (putty in this case) reporting 'Server host key invalid'. The solution was to change the Encryption preference order here in putty:
The most common cause of this is: the anyconnect (webvpn - enable <interface>) being enabled on the same interface as the interface you are trying to use for the ASDM (http <ip> <interface>)
If your using bridge-domains on IOS-XE then you can check the mac-address table instead: #show bridge-domain0 28CD.E00A.41B7 forward dynamic 61 TenGigabitEthernet0/1/0.EFP47 Then check DHCP is you have it running: #show ip dhcp binding | inc 41b7192....
It seems like the ASA is trying to explain (especially through packet tracer) the destination IP address is not available based in the ARP cache.
If the destination IP address were learnt via ARP then this will likely resolve your issue.
Just con...
