I have some dumpfiles. from 4 bitcoin installation on my W1ndows 10 desktop. I am running the latest version. The dumpfiles  where created with the previous version-

when running the command "importwallet" I get 2 different responces.

"null"  which I interpret as  OK

"Error: std::bad_alloc"  which I do not understand.

I have checked the input files and they  look ok

Suggestions?