Primary filegroup is full SQL Server 2008
Follow these steps:


Identify how much space you want to add to the database storage allocation: 

Open windows explorer 
Right click on the disk drive that your database files exist on 
Select properties 
Check how much disk space is available and decide how much of this you want to allocate for the database 
(Suggestion: Leave at least 20% disk space free if you house the database files on the same disk as your OS {Sub-Suggestion: Don't do this! Rebuild/migrate your data to it's own disk; you're screwing yourself on I/O.} and leave at least 8% for a pure data disk; these numbers are estimates of what I think the actual percentage suggestions are.)

Update the storage allocation for the database.

Open SSMS 
Click the "View" tab 
Select "Object Explorer"
Expand the "Databases" folder 
Right click the database your trying to bulk insert into 
Select "Properties" 
Click the "Files" list option from the "Select a page" area at the left of the properties window 
Find the "Database files" row with the "Filegroup" as "PRIMARY" 
Add whatever number of megabytes you want to add to the database allocation to the "Initial Size (MB)" number 
Hit "OK"  (You might also want to consider your "Autogrowth" values while you're here.)



You want to give your database as much storage allocation as you can afford to give it. If it runs out of space you'll receive this error without auto-grow on and if auto-grow is on you'll take a performance hit each time it has to auto-grow. If you are simply out of disk space then that is your answer and you need a bigger disk.