Update: Apple has released this knowledge base article addressing this issue. The iTunes 9 iTunes Store will not work with developer's copies of Snow Leopard. In order to access iTMS, users with developer's builds of Snow Leopard must upgrade to retail release versions.
The excitement of downloading iTunes 9 yesterday quickly faded as I encountered a strange error. What started as curiosity over the new look of the iTunes Music Store soon became a still unsolved battle with the following error message:
So, before I checked out a single feature of the new iTunes, I started troubleshooting it. I clicked the option to "Open Software Update" thinking that perhaps I had not updated. Sure enough, I was met with:
So my first thought, and hope really, was that this was a simple permissions error that Disk Utility could solve. Unfortunately, this was not the case. After verifying the permissions and the disk, the error continued.
My next step was to reinstall iTunes. Again, no luck. I then created a new user to see if my issue was system-wide. The same error appeared on my test user and I was still no closer to figuring out a solution. I attempted to download and install a fresh copy of Safari 4.0.3, however, the versions available for download from apple.com are not able to be installed on Snow Leopard.
I clicked through and attempted to change security settings in both Safari and iTunes, all to no avail. I did realize though, as some Apple Support Discussion forums users noted, that although most of the iTunes Music Store could not be accessed, I was able to get into my account settings as well as the iTunes U. section of the store. It was this discovery that leads me to believe the issue is with the iTunes Music Store and how it is interpreting what browser I have installed. I will continue to look into this issue and post an update as soon as a solution is come by. In the meantime, if you have experienced this issue and have a workaround or solution, let us know in the comments!
Test Environment: Black MacBook running Mac OS X 10.6 (10A421), Safari 4.0.3 (6531.7), and iTunes 9.0 (70)