This arstechnica article describes the basic steps:
Start by visiting the program portal
and make sure that your developer
certificate is up to date. It expires
every six months and, if you haven't
requested that a new one be issued,
you cannot submit software to App
Store. For most people experiencing
the "pink upload of doom," though,
their certificates are already valid.
What next?
Open your Xcode project and check that
you've set the active SDK to one of
the device choices, like Device - 2.2.
Accidentally leaving the build
settings to Simulator can be a big
reason for the pink rejection. And
that happens more often than many
developers would care to admit.
Next, make sure that you've chosen a
build configuration that uses your
distribution (not your developer)
certificate. Check this by
double-clicking on your target in the
Groups & Files column on the left of
the project window. The Target Info
window will open. Click the Build tab
and review your Code Signing Identity.
It should be iPhone Distribution:
followed by your name or company name.
You may also want to confirm your
application identifier in the
Properties tab. Most likely, you'll
have set the identifier properly when
debugging with your developer
certificate, but it never hurts to
check.
The top-left of your project window
also confirms your settings and
configuration. It should read
something like "Device - 2.2 |
Distribution". This shows you the
active SDK and configuration.
If your settings are correct but you
still aren't getting that upload
finished properly, clean your builds.
Choose Build > Clean (Command-Shift-K)
and click Clean. Alternatively, you
can manually trash the build folder in
your Project from Finder. Once you've
cleaned, build again fresh.
If this does not produce an app that
when zipped properly loads to iTunes
Connect, quit and relaunch Xcode. I'm
not kidding. This one simple trick
solves more signing problems and "pink
rejections of doom" than any other
solution already mentioned.