reinstaling adobe Acrobat Professional 9.0 International English Windows

Ok. I strongly suspect you should have preserved the installer when it was still supported (which it hasn't been for years). But several times I have seen an Adobe person here who could fix this, but not in many months. Volume licensing is a special world and only a few know it. If you want to attract his attention I suggest you start a new topic which includes all the key information you've given over many posts and mentions the volume license portal and Acrobat 9 in the subject. Perhaps it will be seen over the next few months but I recommend you also consider a plan B.

So you are logging in to the volume license portal, but it's not there?

assuming you're using a valid adobe serial number (6 groups of 4 numbers), you have a mismatch between your installation file and serial number.  ie, you can have a valid serial number, but if it's for program A and your installation file is for program B, you will see an invalid serial number message.

common mismatches are language/region (eg, serial number is for western europe and installation file is eastern europe), platform (eg, serial number is for a mac and installation file is win), license type (eg, education vs enterprise vs individual).

and one of the most common is using a program installation file with a suite's serial number. eg, using a cs6 suite serial number with a photoshop cs6 installation file.  that won't work even though photoshop is included in that suite.  you must use the suite's installation file (and you can choose to only install one program from the suite).

here's official info about that error,  http://helpx.adobe.com/creative-suite/kb/error-serial-number-valid-product.html

[moved from Downloading, Installing, Setting Up to Installing, Updating, & Subscribing to Acrobat]