Firefox problem: web server checking Acrobat plugin

298 · 03-25-2008, 10:28 AM

My company is using an extremely picky online service for our salary statements. Previously it refused my logon attempts because I was not using Windows and IE. This was easy to circumvent with the "User Agent Switcher". Now it doesn't let me in because it thinks I don't have Acrobat. Is there any way to spoof that? (Actually, I do have Acrobat Reader 8 and the FF plugin is working fine.)

ophirg · 03-25-2008, 10:41 AM

in FireFox:
Edit menu -> Content(tab) -> File types -> Manage
choose PDF and click Change Action
You can then tell FireFox to use a different method to open PDF files
does that answer you question?

298 · 03-25-2008, 10:49 AM

Not really. acroread is set to handle pdf files. I don't have a problem with pdf files. It's that Microsoft invested server that refuses service because it thinks I don't have any acrobat reader. When I go to the logon page with FF, it tells me to install Acrobat and refuses logon. If I do that with IE in Windows, everything is fine.

ophirg · 03-25-2008, 10:56 AM

Are you sure it isn't a problem of browser/os identification?
If I need to use Windows/IE limited web pages I use Konqueror and use Change Browser Identification in the Tools menu.
I'm sure there is an option to do this in FireFox(maybe in about:config?)

298 · 03-25-2008, 11:44 AM

Yes, it is some kind of browser identification. As I said, I get around the IE/Windows requirement using a Firefox plugin called "User Agent Switcher." That lets me pretend to be whatever and it's probably the same thing as the Konqueror function that 'ophirg' mentioned. This takes care of the OS/Broswer question.

But after that there is still something else going on where the server asks the client or where the client reports whether it has Adobe Reader or not.

To make this even more clear: the logon page of this service displays a yellow box "System Requirements". As long as they are not met, it won't let me log on. I got around the browser and OS requirements, but now it bugs me about Acrobat Reader.

298 · 03-25-2008, 12:42 PM

I started to examine the source of that web page. They're checking the Acrobat Reader version using the java script included below. 'ActiveXObject' sounds a bit too microsoft for my taste...

Code:

// Check Acrobat

var adobe_passed = false;
var adobe_version = 0;
	
var strCtrl = "AcroPDF.PDF.1";

try{
  var objTmp = new ActiveXObject(strCtrl);
  if(typeof(objTmp)=="object")
  {
    adobe_passed = true;
    adobe_version = "7";
    objTmp = null;
  }
}
catch(e) {
}
finally {
}   

if(adobe_passed==false)
{
  strCtrl = "PDF.PdfCtrl.";
  var num;
  for(num=6;num<10;num++)
  {
    try{
      var objTmp = new ActiveXObject(strCtrl+num.toString());
      if(typeof(objTmp)=="object")
      {
        adobe_passed = true;
        adobe_version = num.toString();
        objTmp = null;
        break;
      }
    }
    catch(e) {
    }
    finally {
    }   
  }
}

if(adobe_passed==false){
  document.getElementById("acrobat0").style.display="block";
  failed_test++;
}
else{
  if (adobe_version == "6") {
    document.getElementById("acrobat2").style.display="block";
    failed_test++;
  }
  else { // Don't display message in Adobe 7.0
    //document.getElementById("acrobat1").style.display="block";
  }
}

ophirg · 03-25-2008, 01:09 PM

If your service provider is actively forcing you to use software you don't want to use, drop the service provider. You are not the service provider, they are.
You are promoting someone who does something you don't believe in. Paying for someone to limit you is not good policy.

kossi · 08-14-2015, 11:32 AM

just to blow off steam and see if somebody has an idea. exactly same thing here with my bank (bamcomer). these suckers want this stupid adobe reader installed to let me download my bank statements. their answer to my complaint was, well, so download it or don't get your statements. idiots. but however, has meanwhile somebody gotten around this software check, or maybe found a way to send a false flag to their server to pretend that shitty program is installed?

John VV · 08-14-2015, 07:28 PM

there are still a ton of sites that think "internet Explorer 6" IS great