Hello fixthefernback,

To begin with I would recommend that you try to verify the integrity of the game cache:

1. Start Steam and right click on DayZ in your game library (make sure that the game is not running).
2. Select the tab labeled "Local Files".
3. Click on the button labeled "Verify integrity of game cache...".
4. Start DayZ once the process is complete.

If this does not solve the problem, then try to un-install and re-install Steam, and subsequently upgrade DayZ to the experimental version.

Regards,
JStewart

I have same issue and reported following on Steam in first instance:

Tried 4 times now to go on Experimental. Checked that Dayz (experimental) fully downloaded, even rebooted entire PC, but when I click on launch game I see the Steam 'launching game' window for 1 second then it's gone and nothing further happens. I can go back to stable 0.50 with no issues.

I have verified file integrity on each occasion with no issues, so it doesn't appear to be corrupted files.

Anybody else experienced this? and anybody got any suggestions on how to correct whatever is the issue?

Thanks in advance :)

To JStewart @ Bohemia Interactive: I have verified integrity of game cache on each try and have also uninstalled (all files and registry entries) and reinstalled Steam to no avail.

@charlieatlas: do you have any files in your "C:\Users\<username>\AppData\Local\DayZ" folder?

@JStewart: I have files in C:\users\alan\appdata\local\dayz

Contains:
BattlEye Folder
MPMissionsCache folder
Dayz.bidmp
Dayz.mdmp
Dayz.RPT

@charlieatlas: Looks like DayZ has been crashing. Please submit a seperate ticket for that and attach the C:\Users\<username>\AppData\Local\DayZ folder in a .rar archive as well as a dxdiag report.

@JStewart - where do I find the dxdiag report pls?

@charlieatlas: You can create the report by performing the following steps:

1. From the Windows desktop, press the Windows key and the R key to open the Run window.
2. In the "Open:" field of the Run window, type "dxdiag." Click OK or the Enter key to open the DirectX Diagnostic Tool (if prompted to check if your drivers are digitally signed, click Yes).
3. In the DirectX Diagnostic Tool window, click the "Save All Information" button.
4. In the "Save As" window, the DirectX information will be saved as a text (.TXT) file. Designate where the file will be saved (such as the Desktop or other easily accessible location) and then click on the "Save" button.
5. After you've saved the file, please attach it to your ticket.

Hello again,

Closing ticket due to inactivity. However, in case the problem persists, please feel free to open up a new ticket in the Feedback Tracker.

Regards,
JStewart