Hello Mat,
For each of your PKCS #12 files, you could try the following: issue the command certutil -asn <filename> | findstr /i "pb aes des sha"
(replacing "<filename>" with the name of the PKCS #12 file).
If the output starts like:
| | | | | ; 1.2.840.113549.1.12.1.3 szOID_PKCS_12_pbeWithSHA1And3KeyTripleDES
then it should be possible to import the PKCS #12 file into Windows 2016.
If the output starts like:
| | | | | ; 1.2.840.113549.1.5.13 szOID_PKCS_5_PBES2
| | | | | | ; 1.2.840.113549.1.5.12 szOID_PKCS_5_PBKDF2
| | | | | ; 2.16.840.1.101.3.4.1.42 aes256
or similar, then the PKCS #12 file probably cannot be imported into Windows 2016 using the built-in Windows 2016 tools. You will have to recreate the PKCS #12 file using TripleDES and SHA1.
Gary