I have downloaded Pro XI. When I try to use it, I'm asked for the serial number of the previous Rea

[Bella1234]

I cannot use Acrobat Pro XI as I do not have previous Reader serial number.  It is asked for to validate the product.

[pwillener]

This means you have purchased an upgrade from a previous version, not the full version.  To validate the upgrade you need to provide the serial number from the upgraded version.

[Bella1234]

I do not have the serial number of the old product.

[Ned Murphy]

Check your Adobe account online.  If you registered the original product the serial number for it will be listed there.

[Bella1234]

I have searched my account and there is no serial number for my passed purchase. The invoice number was 606828646, date 06/06/2013, order number 126171937, customer number 292951778. This information was from the innvoive.

[pwillener]

Maybe Adobe Customer Support can give you the serial number from your purchase: http://helpx.adobe.com/contact.html?product=acrobat&topic=serial-number-issues-or-activating-my-prod...

[Bella1234]

All I can find is that it was a subscription and there was an invoice with no serial number.

[Bella1234]

I have paid for acrobat and cannot open any pdf. I have to assume that the previous versions of adobe I had was not registered, but I paid a subscription for them. Please send me a solution for the problem as soon as possible.

[Jeff A Wright]

Bella1234 do you have a subscription to Acrobat or a serial number for Acrobat?  Regardless once you enter the serial number or your Adobe ID it will be necessary to activate the software.  I would recommend reviewing the steps listed in Sign in, activation, or connection errors | CC, CS6, CS5.5 - http://helpx.adobe.com/x-productkb/policy-pricing/activation-network-issues.html.  If your computer has been configured to block access to our activation server then it could cause a prompt for a serial number.