Acrobat X Pro became trial version after 4 years. How is this possible?

[alanp89349177]

I had Acrobat X Pro installed on my ultrabook in 2012.  There was no problem until today, when a prompt came up and said this was a trial version. This leaves me with 2 problems:

1. I have no clue where to find the serial number to add to this trial so it can move forward and I can work.

2. If I want to upgrade, I need a serial number from the old version.  Where can I find this information?

[kglad · Accepted solution]

if you purchased from or registered with adobe, Adobe ID

and there's an outside chance your serial number is retrievable from your current install, http://www.belarc.com/free_download.html