Updating Light Room 6 with the latest Light Room

[#1]

I just purchased and downloaded the latest Lightroom software. I have LR6 and have had it for a few years. The older version is associated with an old email address so I no longer log on, provide a seriel # to verify the account. How to I get the new version to update with the older version so I don't have to start from scratch with my photos?  

[#2]

I just purchased and downloaded the latest Lightroom software. I have LR6 and have had it for a few years. The older version is associated with an old email address so I no longer log on, provide a seriel # to verify the account. How to I get the new version to update with the older version so I don't have to start from scratch with my photos?  

[#3]

It would be well if you would clarify what the "latest" Lightroom software is. What is the exact version number that you have installed? Lightroom no longer installs with a serial number. You need to have a Adobe ID and password. If you installed Lightroom Classic then the first time you start that program it should recognize your old Lightroom 6 catalog and prompt you to allow it to upgrade the catalog. You should allow that to happen. That will allow Lightroom Classic to create a new copy of the catalog that will contain all of the work you have done previously, but will be compatible with Lightroom Classic. Once that upgrade is complete Lightroom Classic should start, and you should be able to begin right where you left off, but with the new tools/features that are now available. So please clarify what version you have installed. We need to know the version number.

[#4]

There are two versions of "the latest Lightroom software", so knowing which one you have is crucial. "Purchased and downloaded" does no longer apply. Lightroom is by subscription now. There is a 'Lightroom plan' subscription which includes Lightroom desktop, a brand new and different kind of Lightroom. You probably don't want that, at least not if you want to 'simply move on' from Lightroom 6. And there's the 'Photography plan' subscruption, which includes Lightroom Classic. Lightroom Classic is the predecessor of your Lightroom 6. It can simply open your old catalog, upgrade it and keep working with it.