Make sure that your location is set appropriately in your user profile and on the transaction window. All transactions must be processed through a location that is appropriate for you.
It means there are data issues on the customer record. Click the blue customer name in the common area at the top of the screen to be taken to the Customer Maintenance window, and fix it there. For more information, see Errors, Discretionary Edits, and Warnings.
The red background is the least significant kind of warning. You read the message, and then proceed with the transaction. The pink background usually requires you to click Acknowledge before continuing with the transaction. For more information, see Errors, Discretionary Edits, and Warnings.