i need help with migrating from 139 to 151 -- help bring customers files over

My issue: :frusty:
I recently installed v1.5.1 via my hosting company script installer. (Called Quick Install)
I was previously running 1.3.9h which was installed via Fantastico.
I want to pull over all products, desccriptions, orders history, and customers to the new installation.
Im not sure if any of the above matters, but I figured that I would at least get out all information.

What I have done:
I searched this forum and found: "http://www.zen-cart.com/showthread.php?166512-Fresh-install-on-new-server-but-want-to-migrate-customers-and-products"

(I made backups of everything, backup of the databases of both the old and newly setup carts as well so that I can go back in case of problems...and thank the lord I did...everything is good on that end.)

I did the database backup of my old working cart (139) through the phpMyAdmin software in my CPanel dashboard as per the forum thread.
I then put that database into where the new carts database was.

I also uploaded the file "fix_cache_key.php".

Outcome:
Once I did the above, when I go into my browser to actually see the cart, I get this:
"WARNING: An Error occurred, please refresh the page and try again"
I even tried to follow the "fix_cache_key.php" file and to no avail, nothing will show up and I just get the same error. If I want to actually get back into the admin panel, I have to go into phpmyadmin and restore the backup I made before I started messing with all of this.

Request:
It has been 5 days now of me trying to get this to work. I am getting desperate and would take any advice that I can get on getting this working. Thanks in advance.

The following article may be helpful: How do I rebuild my site? Note in particular the "once you're ready to "go live", your temporary "new" store will be out-of-date" section. This is the easiest way to pull in customers, orders, products, categories, etc.

I'd also advise against EVER using the "script installer" from hosting providers, especially when you want to upgrade to a new version. Instead download Zen Cart from this site and use the included installer (zc_install). The included installer includes (among other things) code to handle upgrading the old 1.3.x database to 1.5.1.

Im going to try out what you suggested now.

Just for clarification, I would never do an "upgrade" via a script installer. Only a fresh install....I don't trust them...personal opinion. Thanks...i'll report back once I see how things go with that link.

this is what I did. I followed what was written there already, did it again to just be sure.

Does anyone else have any input on this??

Mod's, please close this thread. I am starting a new thread with a more direct question. thanks.