No, do everything on the NEW computer. Run the program, go to the menu. Select Help > About Poker Tracker. A window will open. Send the product ID from that window on the support ticket. Then do the steps in the FAQ link.

Here is the FAQ for moving your databases:
viewtopic.php?f=42&t=2334

Then you'll need to create a new support ticket with your new product ID so we can send you a new registration code.
https://www.pokertracker.com/support/ne ... cat_id=123

2+2
http://forumserver.twoplustwo.com/

PTS will no longer be supported as of May 1. No new enhancements will be added to the program.

Create a new support ticket and attach it there.
https://www.pokertracker.com/support/?cat_id=142

This is the PT Stud forum. Please post your issue in the PT3 forum.

Yes.

OK, the format is not even close to what PTS looks for, but depending on how many hands you have you could open the files in Notepad and replace the first line of every hand so that it goes from this: Full Tilt Poker Game #28301988378: Table Edith - $2/$4 Ante $0.40 - Limit Stud H/L - 09:44:55 EET -...

Please post one of the hand histories here that won't import.

However im having difficulty figuring out how can I import those old fails into my database.

Make sure you have the latest patch, then move the hands that failed to import back into your FT hand history folder and force the import again.