Having crash issues, "DunDefGame.exe has crashed" when loading into maps

[Spurlock]

Hello,

Every time I start up the game, it goes to the title screen and I can select the play type (local or via internet) and my character, and I can get into the tavern. When I try to load up a game map it gives me the error "DunDefGame.exe has crashed" and closes. When I use steam to validate the files after it crashes it always tells me there are one or two files that weren't found and replaces them, and this usually does not let me get into a game.
Every now and then, I have not been able to figure out why, it lets me get into a game and I can play several games and go to the tavern and back into games without a problem. When this happens and I go back to the title/menu screen I can not get back into the tavern without the game crashing and giving me the same error message.

These are my system specs, sorry if I link more than is necessary but I don't do this often:

OS Name Microsoft Windows 7 Home Premium
Version 6.1.7601 Service Pack 1 Build 7601
Other OS Description Not Available
OS Manufacturer Microsoft Corporation
System Name SPURLOCK-PC
System Manufacturer TOSHIBA
System Model Satellite L655
System Type x64-based PC
Processor Intel(R) Pentium(R) CPU P6200 @ 2.13GHz, 2133 Mhz, 2 Core(s), 2 Logical Processor(s)
BIOS Version/Date INSYDE 2.80, 7/3/2012
SMBIOS Version 2.6
Windows Directory C:\windows
System Directory C:\windows\system32
Boot Device \Device\HarddiskVolume1
Locale United States
Hardware Abstraction Layer Version = "6.1.7601.17514"
User Name Spurlock-PC\Spurlock
Time Zone Central Daylight Time
Installed Physical Memory (RAM) 4.00 GB
Total Physical Memory 3.80 GB
Available Physical Memory 2.12 GB
Total Virtual Memory 7.60 GB
Available Virtual Memory 5.37 GB
Page File Space 3.80 GB
Page File C:\pagefile.sys

EDIT: I have emailed support, I was just posting on here to see if anyone had potential fixes that could get back to me faster.

EDIT 2: If it helps or adds anything, it seems that I can almost consistently play if I start with the first level and work through them to get to the other levels (that is, when I beat the first level I can move on to the 2nd, when I beat the 2nd I can move to the third). I cannot skip levels (i.e. if I try to load the 2nd level it crashes). That might not help, but I figured it was worth mentioning just in case.

[zammity]

What anti-virus do you use?
Have you checked your firewalls?
Try run it as administrator(if not already tried)

[Spurlock]

I checked the firewall and it says that Dungeon Defenders is allowed. I use Microsoft Security Essentials for anti-virus, and I have tried running it as administrator.

If it helps at all, and I think this might be coincidence, but when I choose my Countess as the character it seems to run into the error more often than when I use other characters.

[zammity]

Do your Microsoft Security Essentials have a built-in firewall?
If it has, check if it is listed as not allowed.
If this doesn't help, you just have to talk with Trendy support

[Spurlock]

I just tried allowing it through MSE, and I'll wait until Trendy gets back to me with an email. Thanks for the help. If it helps or adds anything, it seems that I can almost consistently play if I start with the first level and work through them to get to the other levels (that is, when I beat the first level I can move on to the 2nd, when I beat the 2nd I can move to the third). I cannot skip levels (i.e. if I try to load the 2nd level it crashes). That might not help, but I figured it was worth mentioning just in case.