Open your company file and hit ctrl+1. 

You can still run a company file with the size more than 1 GB on QBD Enterprise without any issue. As the first troubleshoot, run the Verify/Rebuild Data utility regularly (e.g once a month). If the the same error persists, consider to condense your file. Another option, consider buying a 3rd party service to optimize a file. QBD data files larger than 500MB need to be optimized every 6-12 months to ensure they run at top performance. There is no internal functionality in QBD to optimize the data file other than running a condense. The optimize operation will copy all data into a new data file, remove unwanted temporary data, and audit trail data to bring down file size by 25-40%. This will improve the performance and stability of the data file.