Shouldnt the message be "failed to update menu ITEMS" not menus

Updated error messages based on suggestion made by @brianteeman .

Please alpha order the new string:
It should come just before JLIB_INSTALLER_ABORT_CREATE_DIRECTORY

JLIB_INSTALLER_ABORT_COMP_UPDATESITEMENUS_FAILED="Component Install: Failed to update menu items."
JLIB_INSTALLER_ABORT_CREATE_DIRECTORY="Extension %1$s: Failed to create directory: %2$s"

@infograf768 I ordered them based on lines 422-423 (admin file, few lines above my change):

JLIB_INSTALLER_ABORT_ALREADYINSTALLED="Extension is already installed."
JLIB_INSTALLER_ABORT_ALREADY_EXISTS="Extension %1$s: Extension %2$s already exists."

Where word with letter is ordered before underscore. Name is without space because of the original string just above my check does the same.

My question is what is the supposed order:

• alphabetical ignoring underscore
• underscore comes after letters (PHP sort order)
• underscore comes before letters

I always based my work on:
"Blank spaces between words in a page name are treated as an underscore "_", and are therefore ordered after upper case letters and before lower case letters. Blank spaces after a page name come before any character."
in
http://en.wikipedia.org/wiki/Help:Alphabetical_order

and we use here Upper Case letters.
I use "Sort" plugin in Eclipse, which has automatically ordered the strings this way.
Not a big deal though. :)

Just leave it as is. No big deal.

@test i tested the patch and it resolved the issue for me.

I'd love to get this merged, but don't we need to properly quote column names and aliases? Eg.

->where($db->qn('m.client_id') . ' = ' . $db->q(0))

Or

->update($db->qn('#__menu', 'm'))

This would probably ensure it will work with other db drivers.

Joomla menu library files do not escape names either, so I guess they will work..?

@test i installed a component, created a menu item, then uninstalled, and reinstalled it.
without the patch, i got the Component 'com_extension' does not exist message in the menu items backend page.
Same process with the patch works as expected, the menu item works properly

@brianteeman should be good to go.

Issue observed without PR
Applied PR and issue resolved

Setting RTC thanks

Merged - thankyou very much!