Taken from another forum/website:
“Status: Service Blocked”
This error occurs when sending emails. The device is not able to receive emails. However, usually the device is able to get online via the Blackberry Browser.
Incorrect Data Plan with Phone Carrier.
If you connect to your company’s BES (Blackberry Enterprise Server), you will need to have a BES data plan NOT the BIS (Blackberry Internet Service) data plan.
After the carrier switches the data plan to the appropriate BES one, you may need to go into Options > Advanced Options > Host Routing Tables and click and choose “Register Now” to update the devices routing tables.
If you still cannot send or receive emails; you may need to rerun the Enterprise Activation.