Random IE7 freeze when opening a PDF from Acrobat 9.1 Pro

Question

We are having problems specifically with a PC with viewing PDF files in IE 7.0.  Now when viewing PDF files
on our special inhouse loan funding site, the browser will freeze and eventually an error message will come up "Internet Explorer has encountered an error and needs to close".
What I tried so far...
-Ran the Adobe update , it installed Acrobat Professional 9.1.1
-Did the Reset under the Advanced tab in Internet Properties.
-Re-enabled the adobe related IE plugins.
-Deleted everything from the users %temp% file.
-Rebooted PC
I've asked our web application vendor if we could use a much better browser such as Firefox, Chrome, or even try IE8, but they said that it's not supported.
The error shown in the application event log is:
Event Type:        Error
Event Source:    Application Error
Event Category:                None
Event ID:              1000
Date:                     6/3/2009
Time:                     3:11:32 PM
User:                     N/A
Computer:          PROC2
Description:
Faulting application iexplore.exe, version 7.0.6000.16827, faulting module acropdf.dll, version 9.1.0.163, fault address 0x0000221c.
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 41 70 70 6c 69 63 61 74   Applicat
0008: 69 6f 6e 20 46 61 69 6c   ion Fail
0010: 75 72 65 20 20 69 65 78   ure  iex
0018: 70 6c 6f 72 65 2e 65 78   plore.ex
0020: 65 20 37 2e 30 2e 36 30   e 7.0.60
0028: 30 30 2e 31 36 38 32 37   00.16827
0030: 20 69 6e 20 61 63 72 6f    in acro
0038: 70 64 66 2e 64 6c 6c 20   pdf.dll
0040: 39 2e 31 2e 30 2e 31 36   9.1.0.16
0048: 33 20 61 74 20 6f 66 66   3 at off
0050: 73 65 74 20 30 30 30 30   set 0000
0058: 32 32 31 63 0d 0a         221c.. 
Followed by:
Event Type:        Error
Event Source:    Application Error
Event Category:                None
Event ID:              1001
Date:                     6/3/2009
Time:                     3:12:12 PM
User:                     N/A
Computer:          PROC2
Description:
Fault bucket 1230219238.
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 42 75 63 6b 65 74 3a 20   Bucket:
0008: 31 32 33 30 32 31 39 32   12302192
0010: 33 38 0d 0a               38..   
Thanks for your help!

Answer 1

Ok, well this is an specialized web based application.  I tried opening the PDF's in a new window on my Windows 7 PC and I got them to open without the infinite loop like on a Windows XP machine.
Because that causes an infinite loop on Windows XP, we need the PDF to display in browser, which causes a conflict sometimes between IE and Adobe dll files.
So I've checked out a file that doesn't normally crash the IE/Acrobat9.4 user and checked the properties.
Application: LiquidOffice Form Designer
PDF Producer: DocuCom PDF Core Library
PDF Version: 1.6 (Acrobat 7.x)
File Size: 253.77 KB
Now here's the properties of a PDF that intermittently crashes IE:
Application: Acrobat PDFMaker 8.1 for Word
PDF Producer: Acrobat Distiller 8.1.0 (Windows)
PDF Version: 1.6 (Acrobat 7.x)
File Size: 272.14 KB
Remember I said intermittently.  That's what's real difficult about the problem.  That same file might open 10 consecutive times before crashing.  OR it might crash on the first try.  When things aren't consistently broken it's very hard to troubleshoot the issue since there is no concrete evidence of a single underlying cause.  If it crashed every single time on that file, maybe we would say that its a corrupt file or there's an issue with the program that produced it.  That's not the case here.
Good idea as to looking at the version.  We could change the versions but we would need to open a request with the application developer, and updates to some of these forms takes weeks for them to integrate.