migrated shop seems to miss core TB files

[Pedalman]

Hi

I migrated PS 1.6.15 to TB1.0 via upgrade module and updated to TB1.3. Since I have at the moment three critical problems on our live shop I thought about comparing core files agains a clean TB1.3 install. I noticed that there seem to be several files left from my older PS1.6.15. Is that possible? I thought that they were all deleted in order to be replaced. Ok, I know this is very general talking, but anyways. Only a few examples of files I got on live server after migration the clean TB1.3 install has not: /DB/DbMySQLi.php /DB/MySQL.php /DB/Discount.php /DB/PaymentModule.php

Files that are in the clean fresh install of TB1.3 and not to be found on live server after migration! /DB/Product.php

Only named a few. My question is now of course what I shall do :)

Is it safe to delete all those files on the migrated shop that are not to be found in TB1.3 clean install (backup is for sure) and to copy those missing from clean TB1.3 onto the migrated live server?

It is my best guess and at the same time I wonder how that could happen?