PC hangs opening a PDF in Thunderbird

[djn]

Hello all. I've been using (and strongly suggesting to friends and family) PDF-XChange for years without a problem - until last Friday, when a friend called for help as his accounting PC got stuck and unresponsive after trying to open a PDF that was attached to an email message in Thunderbird. The viewer launched at full screen as expected, then stopped while displaying an empty white page background, then the mouse cursor vanished from the screen , all attemps to unstuck the PC via keyboard (ALT+Tab, ALT+F4, the Windows key, Win+E, Win+D, ALT+CTRL+DEL) had no effect whatsoever and the only way out was to pull the plug and reboot the machine.

Please note that the PDF file was not the culprit: in my friend's case it was an invoice made by his own accounting software and emailed across the office; in my case it was a file I made and emailed to myself from a 'known good' customer's PC (with a full retail and updated Kaspersky cheching the outgoing mail on the PC and Clamwin doing the same on the server). Both receiving machines (and, in my friend's case, the sending machine too) are fully up to date and protected (up to date AVG, Spybot S&D, MBAM, MBAE, SpywareBlaster, EMET, CryptoPrevent, CryptoMonitor and some other less known stuff) and have been using PDF-XChange for years, no new software has been installed recently and Thunderbird is latest 38.7.0. A check on the running processes and autorun locations (with Sysinternals' Autoruns and ProcessExplorer) did not show anything unusual or unexpected.

More details:
-my friend's PC: Windows 7 SP1, PDF-Xchange 2.5.317 (javascript disabled), Adobe Acrobat Reader DC installed
-my PC: Windows XP Pro SP3, PDF-Xchange 2.5.316 (javascript disabled), no other reader
In both cases both Windows and Thunderbird are set to open PDF files with PDF-XChange.

In my friend's case after the reboot PDF-XChange could not display the contents of other double-clicked PDFs on disk: it just got stuck displaying a white page background. After many attempts (including uninstalling and reinstalling a fresh copy straight from Tracker's website) the problem was solved - using System Restore to bring the PC into the state saved a week ago. Nothing like that happened on my PC.

Got any ideas?

[Stefan - PDF-XChange]

Hello djn,

Welcome to our forums.
Can we get a copy of the file in question to test here at our end?
Also - can you please try installing the Viewer's successor - the PDF XChange Editor:
https://www.pdf-xchange.com/produc ... nge-editor
And let us know if it manages to display your file correctly?

Regards,
Stefan

[djn]

Hello and thank you.

I don't remember which file exactly caused the first carsh, so I just went around Thunderbird in search of a PDF and the one attached below caused my PC to hang just 20 minutes ago. It's a rather plain and lightweight file of 9 pages with nothing unusual in it. The Editor (I have 5.5.311.0) had no problem opening it once I saved it in a folder - but so did the Viewer, which just opened and displayed the thing. It's when interacting with Thunderbird that things seem to go south. To be precise, this time when I opened the attached file straight from Thunderbird the first page got displayed and the crash happened when I was scrolling down to page 2. The scrolling stopped when the edge of page 2 was barely visible, but the PC did not hang immediately: I was able to ALT+Tab across to Chrome (to this very forum), ALT+TAb back to the Viewer and got finally stuck with the last ALT+Tab to Thunderbird - unable to switch out again and even to change application thru the Taskbar. Right-clicking on the Taskbar to force-close the application also did not work: the context menu was not displayed. I waited some time hoping for some miracle and finally rebooted the whole machine.

I have to mention that I managed today to open a couple PDFs straight from Thunderbird without anything bad happening: in all cases the file were single-page PDFs of max 125 kB. I've also had a couple of similar accidents outside of Thunderbird: one trying to open a (very heavy, ca. 80 MB) file from an USB pendrive, ant the other double-clicking a PDF on a network share on my laptop (via WiFi). Could it be a matter of timing when reading a file?

[Patrick-Tracker Supp]

Hello djn,

We use Thunderbird as our preferred email client so I sent myself the file, and opened it up from T-Bird without any issue.

Do you have any add-ons to T-Bird?
What operating system are you running?

Thank you!

[djn]

Here we go again, this time I'm attaching a file that managed to hang my PC three times in a row: first time clicking on it inside Thunderbird, next clicking on it after saving it to disk and finally once more when trying to open it from within the Viewer (via File->Open dialog). Shoudn't be the file itself, I think: it's just an automatically created invoice from Register and there are thousands of people receiving these every day. The Editor had no problem opening it, anyway.

The good news is that after an afternoon of reboots I have tentatively nailed the culprit: MBAE, aka the MalwareBytes Anti-Exploit. I have version 1.08.1.1189 running - stopping it allows the Viewer to display the content without hanging. I believe I have narrowed down the problem to just two protection settings: 'Memory Patch Hijacking Protection' and 'Stack Pivoting Protection' (in Settings -> Advanced Settings -> OS Bypass Protection tab), but I need some more time (and reboots) to be sure about this.

[John - Tracker Supp]

Hi,

I am afraid even if this is our issue - it cannot now easily be resolved as all non critical development of the Viewer has ceased and all team members have moved to its replacement the PDF-XChange Editor which appears to have no such problem - we strongly recommend you move to the Editor if this continues to be a major problem for you.