Since a couple of days it\'s possible to use in-app-billing in Android apps. Very cool of course. So, I started working on a update for my application to implement this. But
I just encountered this issue and realized it was because I was running a debug, unsigned version of my app. In Eclipse, when I exported and signed my application and installed it on the phone, then I was able to use my in-app products without seeing this error message.
I also ran into this problem. I finally realized that my published app had a versionCode of 3, my draft (unpublished apk with the Billing permission) had a versionCode of 4, and the signed apk I was using to test in-app billing was still at versionCode 3. Once I changed the versionCode to 4, I was able to get through to the actual in-app product page for the purchase I was requesting.
My solution was that I needed to use the same key to sign apk in Market (as draft APK), and in test. So instead of just Run Application I always have to export signed APK with every update, uninstall and reinstall it in device using apk command-line commands. In principle you can use your own keystore as debug keystore also, but it requires using specific hardcoded passwords and names for keys.
Thought I'd share one more possible solution if you're getting this error. I originally uploaded to google a draft of my apk with the billing permission enabled, so I was able to set up in app purchasables. Later on I uploaded another apk without the billing permission missing from my AndroidManifest, which resulted in the error. Definitely seems like an unlikely case, but it happened for me so it's possible.
Edit: Along the same fold, if the version you have submitted as draft to google is unsigned, the error will also occur.