Migration Assistant error "firewall being turned on"

Hi everyone.

I have just purchased a new MacBook Pro 16' (2019) running OS 10.15.7 and looking to transfers data from my old MacBook Pro (late model 2008) running OS 10.11.6. Trying to use Migration Assistant but I keep getting an error about the "firewall being turned on" (but it isn't on on either Mac) on the new Mac and the old Mac just continues to say searching for a computer with a spinning wheel of death.

I am also at the cottage with a terrible wifi network. Can someone walk me through using Migration Assistant without wifi and using an ethernet cable. Would that help? I have never before had any issues with the use of MA. Am I missing a simple step?

Help appreciated. Feeling stupid right now.

Steve

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