Did you, under your old system, have any modules that needed compilation (as in used a C compiler)? If so, is it possible that this compilation created a link to the old DLL that has now been removed?

Unrelated suggestion: I had a similar problem when doing something with MariaDB/MySQL. I THINK I installed Maria first, which loaded something that used something 32 bit. Then, when I loaded DBD::MySQL, it defaulted (correctly) to 64 bit and then complained about the DLL. The only way forward was to uninstall Maria and Perl.

These are pretty wild guesses. I hope they're not nonsense, but I offer no guarantees.

Regards,

John Davies