Author Topic: Access violation error every morning (Read 24,646 times)

dlprice · « **on:** April 26, 2012, 04:06 PM »

I leave screenshot capture running all the time on my computer. It seems that every morning (after some combination of the computer going in and out of sleep mode, and logging on and off of our VPN), I get an Access violation error the first time I try using Screenshot Capture.

"Access violation at address 004B32A0 in module 'ScreenshotCapture.exe'. Read of address 00000004."

v3.04.01
Windows 7 Enterprise Service Pack 1

mouser · « **Reply #1 on:** April 26, 2012, 04:12 PM »

Hi Dl.. ok that's troubling, BUT.. also perhaps somewhat good in the sense that it is happening regularly enough that i should be able to attack the problem; something must be happening with sleep mode.. perhaps something to do with monitor info changing in sleep mode and not reseting, or some memory pointer no longer valid after sleep mode.

If you are willing to help me diagnose, I'd love the help trying to test a fix, and i can begin by sending you a debug version that will help me narrow down the cause -- email me: mouser@donationcoder.com.

dlprice · « **Reply #2 on:** April 30, 2012, 09:54 PM »

Probably should have mentioned in my original post that I switch from a dual monitor environment at work, to using just the laptop screen at home. Which would be right inline with your comment of "something to do with monitor info changing in sleep mode".

mouser · « **Reply #3 on:** April 30, 2012, 09:56 PM »

sorry i haven't followed up on this yet -- i'll be working on it in the next couple of days and be in touch -- i have a few more SC things to fix anyway, so expect a new release this week.

dlprice · « **Reply #4 on:** April 30, 2012, 10:27 PM »

No problem. You don't owe me anything. Thanks for the great software.

dlprice · « **Reply #5 on:** June 01, 2012, 09:56 PM »

I am still getting the error "Access violation at address 004B418C in module ‘ScreenshotCaptor.exe’. Read of address 00000004." with v3.05.01 of Screenshot Captor.

It seems to occur under the following senario:

1) Start Screenshot Captor while using dual monitors.
2) Put my laptop to sleep by removing from docking station
3) Awake my laptop using only the laptop screen
4) Put it back to sleep
5) Start my laptop again the next morning in its docking station using dual monitors.

At that point, when I first use Screenshot Captor, I get the error. It seems to clear itself after that.

MortDK · « **Reply #6 on:** June 07, 2012, 11:17 AM »

I experience this exact same issue. Also, seems to happen when running on a laptop using dual screen (external display) and waking up from sleep mode.
Once the error has happened and been dismissed, SC works fine.

Edit: running v3.05.01, Windows 7 on a HP Elitebook 2560p with a Dell external display.

mouser · « **Reply #7 on:** June 07, 2012, 09:48 PM »

I'm determined to fix this bug, and i do have a laptop i can test with..

Can you guys tell me if when you say "when I first use Screenshot Captor, I get the error" what constitutes "when i first use screenshot captor" -- does the error happen just if you try to bring up the program, or at the time you perform a capture? Does it matter if you do a full screen capture or a region or active window capture?

dlprice · « **Reply #8 on:** June 08, 2012, 04:46 AM »

For me, I mean when I first try to perform a capture using the hot key I have triggering "Grab selected region". The program, itself, had remained running in the system tray. The cross-hairs appear, but as soon as I start to select the region, I get the error.

rispav · « **Reply #9 on:** June 11, 2012, 03:15 PM »

Hello, I am also experiencing this issue after hibernation. I am runnig the version 3.04.01 on win 7 and I also have an external Dell display attached as the main screen. my Laptop's screen is secondary. after I Exit SC and start it again, then no problem appears. can I help? do you still need answers to your questions, some more observations? Richard

bubbajunk · « **Reply #10 on:** June 11, 2012, 09:45 PM »

I was about to create a new topic before I found this post thread. I am experiencing the same issue with a different address in the error message. For me the error is 'Access violation at address 004B4948 in module ScreenCaptor.exe. Read of address 00000004.' I am using SC v3.06.01 on Win 7 Enterprise SP1. I am able to consistently replicate the issue.

Like the others here, I initially thought the issue had something to do with coming in and out of sleep mode as that was when I seemed to experience the issue. I've been able to replicate the issue without invoking sleep mode. For me the issue occurs on the first screen capture after undocking. To be more specific, I also have my PrntScrn hotkey mapped to 'Grab Selected Region'. So the first time I hit the PrntScrn button after undocking, I get the error. The behavior for me is identical to that for dlprice. I get the cross hairs and as soon as I try to draw the region box, the error occurs. After clearing the error dialog boxes, the error recurs if I again try to draw a region box while the cross hairs are still present. If I hit the ESC key to dismiss the cross hairs, then subsequent presses of the PrntScrn key don't error.

When docked, I use dual monitors, the primary monitor is connected to the docking station and the secondary monitor is laptop. When I undock, the primary monitor switches to the laptop screen. Perhaps SC gets confused about which monitor is which on the initial capture.

mouser · « **Reply #11 on:** June 11, 2012, 11:07 PM »

Quote

I get the cross hairs and as soon as I try to draw the region box, the error occurs.

that's a good clue..

ok this has moved to my top priority to fix -- i appreciate the replications.

i may have gotten an answer to this before, but can i get some confirmation:

1. does this ONLY happen with selected region capture? i.e. if you do a full workspace or full screen cap or active window capture, does the error also trigger?
2. if it only happens with selected region capture, does it happen on selected region capture if you FIRST do a full screen capture?

alexp · « **Reply #12 on:** June 12, 2012, 08:44 AM »

I've been getting this issue to with my dual monitor setup at work. Some mornings when I come in it's as if my computer has forgotten it's got a second monitor attached and I have to go into screen resolution and detect the second monitor. This issue seems to have been happening for a while but I'm not sure if it's the program that's causing it or an issue with my actual pc. I rarely shutdown/reboot my pc so I might close screenshot captor when I'm done and see if that stops my forgetting monitor issue?

To answer your questions from my experience.

1. Seems to be only happening with selected region capture. I seem to be able to take full screen captures.
2. After taking a full screen capture I'm able to then use selected region capture with no problems.

mouser · « **Reply #13 on:** June 12, 2012, 08:52 AM »

Quote

1. Seems to be only happening with selected region capture. I seem to be able to take full screen captures.

This would be a really big clue -- can anyone else confirm that this is true for them too?

Ath · « **Reply #14 on:** June 12, 2012, 10:24 AM »

Quote from: mouser on June 12, 2012, 08:52 AM

can anyone else confirm that this is true for them too?

+1 here.
I leave my work-PC on over-night, and just turn off the 2 Display-Port connected monitors. They seem to reset the display settings quite rigorously, because any window left open when turning off the monitors is resized to something like 640x480, and into the primary monitor's left-top position.
I tested with Selected region this morning, and it error-ed out. After clicking away the messages, it worked fine in selecting and making the screenshot.
I'll test again tomorrow, creating a full-screen screenshot and then try Selected region, got too many windows open now that I don't want to fix resizing on (can't close 'm either), to turn off the monitors right now

mouser · « **Reply #15 on:** June 12, 2012, 10:27 AM »

Thanks Ath -- but to reiterate, what i need confirmation of is that the only thing that causes the error is a Selected Region capture.

Ath · « **Reply #16 on:** June 12, 2012, 10:47 AM »

Quote from: mouser on June 12, 2012, 10:27 AM

what i need confirmation of is that the only thing that causes the error is a Selected Region capture.

That's what I'll be checking tomorrow...

bubbajunk · « **Reply #17 on:** June 12, 2012, 04:56 PM »

I tried several scenarios. For each scenario, I first docked the laptop, executed a screen capture, undocked the laptop, executed another screen capture. Here's what happened for me for each scenario on the second (undocked) screen capture

- Selected Region - 'Access violation' error as described above
- Screen (current monitor) - Screenshot Captor window presented, looks like a screen capture occured, but nothing captured. After hitting hotkey again, the full screen is captured and displayed as expected.
- Complete Workspace - screenshot of full screen captured as expected.
- Active Window - most of the time this worked, but once or twice the taskbar icon turned red like it was in capture mode, but nothing else appeared to happen. In that case, I had to exit and restart Screenshot Captor.
- Fixed Region - worked as expected

So, I only get the 'Access violation' error dialog box on the Selected Region capture, but there was some other unexpected behavior associated with others.

mouser · « **Reply #18 on:** June 12, 2012, 05:03 PM »

Thanks very much for the report bubba.. that makes things a bit more murky for me, but i'll make another run at solving it!

Ath · « **Reply #19 on:** June 13, 2012, 06:59 AM »

Quote from: Ath on June 12, 2012, 10:47 AM

That's what I'll be checking tomorrow...

Ok, it's tomorrow now

, and I tried PrtScr and Ctrl-PrtScr hotkeys (default key-mappings: Grab current Screen and Grab current Window) without any interaction with SSC after startup (only the systray context menu for hotkey reference), but I got no good capture from both (empty screen, no image saved). But no errormessages either.
Then pressed Shift-PrtScr for a Selected Region capture, and the selection and capture worked both as expected, without errors, giving a saved file in my capture store (default setting of saving the capture to disk).

Quote from: mouser on June 12, 2012, 10:27 AM

what i need confirmation of is that the only thing that causes the error is a Selected Region capture.

I'd say that the answer is: No.

Seems like detecting the available screens after a 'system reconfiguration' isn't working right, until after some part of SSC is actually (re)initializing those parameters. Or maybe the 'DisplaysHazChanged' call-back event isn't set up properly

HTH

bubbajunk · « **Reply #20 on:** June 13, 2012, 02:23 PM »

Mouser, sorry didn't mean to create confusion, was hoping to reduce the confusion by presenting the results from various screen capture modes. What is consistent for me is that I can reproduce the 'access violation' error everytime using 'Selected Region' capture mode after undocking using dual monitors and the 'primary' monitor shifts from the external display to the internal display. What I was trying to show with the other scenarios was that I was not able to reproduce the 'access violation' error with any other capture mode.

Sounds like Ath's experience is similar to mine with some of the capture modes. E.g. After undocking and choosing 'Screen (current monitor)' mode, the edit window is displayed (based on config) but nothing is captured. Maybe if the Selected Region error is corrected, there may be something there that could be impacting the other modes.

mouser · « **Reply #21 on:** June 18, 2012, 08:40 PM »

Ok I think i have it fixed; new version coming up tonight.

mouser · « **Reply #22 on:** June 18, 2012, 11:27 PM »

can you guys try this version and let me know if it fixes:
[beta link removed -- new release is officially uploaded]

Ath · « **Reply #23 on:** June 19, 2012, 07:06 AM »

I just shot this one after I updated (3.07.01) and switched my screens off and back on:

And, Lo and Behold, no crashes!

Seems like you nailed it, great

mouser · « **Reply #24 on:** June 19, 2012, 07:13 AM »

Thanks for the report Ath, and thanks to everyone for their patience and help with this nasty bug.