I can t open with adobe acrobat 8 standard some pdf files but works wiht adobe reader IX

[il38913870oicr]

 I try to open some pdf files with adobe acrobat 8 on an Windows 11 PC, but receive the error:

There was an error opening this document . The file is damaged and could not be repaired.

if I try to open them with adobe reader IX it works. Also if I try to open them on a PC with Windows 10 using Adobe 8 Standard, I can do that.

Any idea why I receive that error?

[try67]

No, and you're not likely to get support for such an ancient version. Why are you using it in the first place?

[Steve39055171mpap]

He's using it because he purchased it when it came out and it does everything that he needs it to do. I'm answering this for il389 because I'm have the same issue. I don't want to pay a monthly fee to use the online version nor do I want to have to purchase another product when I was perfectly happy with acrobat 8. 

[try67]

OK, then you need to accept the fact that some files will not open with it. (Valid) old files will open with a new version, but the opposite is not guaranteed.