I am having exactly the same issue and have spent many hours trying to get my phone activated, but even though it's not on any network the 4s I bought through Sprint will not work.
Yes, I am still having issues. I've tried Best Buy, Corporate Store and CS on here with no luck.
It says there is an error activating the phone. I have had several CS, Best Buy and two stores try now with no luck. There is an open ticket on this and they said it would be fixed in 24 hours and it is still not fixed.
I am having a similar problem. I have an iPhone 5 that came from sprint, then I activated on freedompop. Now I'd like to go back to sprint but when I called the sprint customer care they said it was a prepaid serial number. then after going to a store they said it was not a prepaid phone (apparently it doesn't include iphone 5) so I couldn't activate it prepaid.
So what happened to the serial number? How can I activate it with sprint?
Once a device is flashed over to another provider, we can not guarantee that we will be able to activate it again on the Sprint network. If you would like, we can check the serial number of the device to see if there are any restrictions. If you would like us to do that, please send us the info via private message. You can PM here http://bit.ly/1qQty1X.
Sprint Social Care
I know this is an old thread but I'm having trouble activating a device that was previously on freedompop as well. It is a Samsung Galaxy S3 but the previous owner told it was never flashed off of Sprint because Freedompop does not require that. A Sprint rep told me it had been flashed off of Sprint and they were unable to reactivate it. I'm finding different answer everywhere. How can I find out if my phone can be reactivated or not?