Windows 7 64-bit Error -1856

Is there a fix for this issue? Please don't say turn UAC off

Not actually a fix (I'm never sure which ACLs are causing the trouble in these cases), but a safer workaround perhaps. You can set your QuickTime Player to always run as an administrator.

Right-click your QuickTimePlayer.exe at:

C:\Program Files (x86)\QuickTime\QuickTimePlayer.exe

... and select "Properties". In the Compatibility tab, check "Run as Administrator" and click OK.

Does that get you past the error? Or do you now get different errors when trying to launch the QuickTime Player, now?

I'm afraid I can't speak for them ... we're a user-to-user troubleshooting forum here.

If you'd like to get some input directly through to the developers, or check to see if the bug has already been reported, you could register (for free) as an Apple Developer:

http://developer.apple.com/programs/register/

... and then file a report via the Apple Bug Reporter:

http://developer.apple.com/bugreporter/

100% repro of the same problem. Removal of all apple sw (as seen in other posting of this problem) and reinstall doesn't help. Still 100% repro.

Unfortunately, running as admin is a workaround, not a fix. If quicktime is attempted to be called by 3rd party apps (not itunes) quicktime fails. And since the EXE isn't directly called, the "running as admin" workaround doesn't work.

Google queries show a growing number of problems with Quicktime on Win7 x64 giving this error.

Adding my voice.

Unfortunately, running as admin is a workaround, not a fix. If quicktime is attempted to be called by 3rd party apps (not itunes) quicktime fails. And since the EXE isn't directly called, the "running as admin" workaround doesn't work.

Many thanks for the heads up ... which sorts of third party applications are you getting that with? Adobe Creative Suite, for example?

Another possible workaround is to run QuickTime normally in a different Windows user account on the PC. (That can dodge the troublesome ACLs causing the trouble in the usual user account.)

So by extension, if you run the third-party app in a different user account (in which QuickTime isn't getting the 1856), does that get you past the QuickTime failure?

I just started getting this same error recently on Win7 x64. I can start the player itself fine, even without admin settings, but trying to play a .mov file either from within the player or through browser plug-ins (Fx, IE, Chrome) results in the Error -1856 issue. Adding in running as an administrator does nothing. When it first cropped up, I was on the version before the current one, but updating to the latest did not fix the problem.

Haven't found any other solutions out there yet. I haven't tried fully uninstalling, wiping all traces, and reinstalling and might end up doing it. I like my HD trailers.

[Edit] The full uninstall/reinstall did not fix the problem.

Message was edited by: Equisilus

An additional followup to my above post: I determined that I could get the combo of running both the browser and Quicktime, both as an admin, to bypass the error and have mov files play. Not a good workaround, but it's possible, at least.