What setting will convince Windows menus to appear to the right, instead of left?

Just recently, the right-click context menus in Windows 7 have been acting in a kind of left-handed way. That is, when possible, the initial menu appears to the left of the mouse pointer. When I hover over a submenu option, the next level of context menu appears to the left of the first and so-on.

Basically, what normally happens when you're right at the right-hand edge of the screen is happening all the time - except when I'm at the left-hand edge. Perhaps it's some kind of left-handed users option, but that doesn't seem likely - more like a right-to-left language option, except that I've never even tried to use a right-to-left language.

I haven't checked every app. for the issue - probably only Windows Explorer, definitely not in Firefox, for the moment that's as far as I've checked.

Scratch that - this affects menu bars as well as context menus. The menus dangle down to the left of the menu-bar item instead of the right, and submenus open to the left too. This seems to apply to most applications, but not too Firefox or Thunderbird.

I find this extremely annoying.

I have no idea how this occurred, though it isn't the only weird glitch I've had in Windows 7 in the last few days - see Can anyone explain this weird sound-card glitch? (already fixed, but not explained)

I assume there's a setting somewhere that has got changed, but I can't find anything. There's also a chance that I've suffered some kind of registry corruption, so I might need to apply a fix in the registry - not something that scares me, but I need to know what to fix and how.

So - does anyone know what setting has been changed, and how I can fix it?

Also, beyond CCleaner (which I already have), are there any tips on making sure that the registry stays clean and sane?

Finally, both Microsoft Security Essentials and Malwarebytes Antimalware seem happy that I don't have a malware problem. Should my recent glitches make me doubt that?

Solution 1:

My Windows 7 does this as well, as long as there's room on the left (to the edge of the monitor), if not, they slide out to the right. Weird, and I can't say for sure if that's 'new' or if I just never noticed. :)

I found this article on SevenForums from 2008, so it's not too new:

How to Set Windows 7 Menus to Open to the Left or Right Side

Basically there's a registry key: HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows\MenuDropAlignment

If it exists and is set to 1, then the menus will favour sliding out to the left. If you remove the key (or set it's value to 0) it will slide out to the right.

You'll have to logout and in again (or reboot) to make the setting take effect.

I don't think that key is there by default but as I said I'm not sure, and I couldn't even begin to imagine how I'd figure out when/how it got added.