change of ip address

[mdbarber]

not sure where to start but will keep it short here, can add more detail 
if required.
initial setup of ubuntu in a VM with dhcp, most things working fine, 
change to static IP and initital connection to guac ok but guacamole rdp 
connections fall over with simple time out error messages
change back to dhcp and after refreshing mac addresses in VM works fine 
again.
any ideas where to start looking?
tia
mdb

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