Adobe Acrobat 9 Pro not allowing to be reader enabled

[jude_h1]

I had created an invoice form in Adobe Acrobat 9 with minor coding a while back, which has been used by another person for years with Reader 8, both older Windows computers (creator is XP and user is Vista). Never had any problems. Suddenly on 1/9/23, the user with Reader 8 can't fill in or use the form at all, and gets this message:

"This document contained certain rights to enable special features in adobe reader. The document has been changed since it was created and these right are no longer valid. Please contact the author for the original version of this document."

I am the author and didn't make any recent changes. Any minor changes in the past were never an issue. Now, I can't even extend features when I try to resave to solve this, I get "This document cound not be Reader Enabled". 

What is going on? This is extremely annoying, like some expiration date stopped everything. Thanks for any help to solve this.

[kglad]

do you have an old os that prevents you from upgrading?

in the future, to find the best place to post your message, use the list here, https://community.adobe.com/

p.s. i don't think the adobe website, and forums in particular, are easy to navigate, so don't spend a lot of time searching that forum list. do your best and we'll move the post if it helps you get responses.

<moved from using the community>

[jude_h1]

Yes, they are older OSs on both computers (XP and Vista) that aren't likely good candidates for any further upgrades. These computers are mainly used for basic interoffice work and not online. The "Vista" person does not do anything beyond filling out his invoices, so a computer upgrade wasn't necessary as it worked just fine (..not broke..). Someone had mentioned a possible expiration on a certificate. I purchased the Adobe Pro 9 with the Adobe package, so can they just halt the abilities of the owner of a functioning program? I did try resaving an extended file with Pro DC from a newer computer for the Visa person, but it did not work (received same message as before) and I am unable to install any other version of reader (beyond Reader 8) on this computer. Thanks for any further help with this.

[kglad]

i don't think adobe did anything to explicitly stop your workflow, but you probably no longer meet current security standards.

[Test Screen Name]

Yes, an expiration date on the certificates used. The fix is to use Acrobat Pro DC and Acrobat Reader DC. This is probably dead forever for you on the old systems you use. I don't say this is a good thing.

[jude_h1]

I purchased the Adobe Pro 9 with the Adobe package, so can they just halt the abilities of the owner of a functioning program? I did try resaving an extended form file with Pro DC from a newer computer for the "Vista OS" person, but it did not work (got same message as before) and I am unable to install any other version of reader (beyond Version 8) on that computer. Thanks for an further help with this.