Here’s how you delete a sales opportunity in SAP Business One:
1) From the Modules tab inside SAP Business One navigate to: Sales Opportunities > Sales Opportunity
2) The Sales Opportunity window will pop up. Browse to the sales opportunity you want to close. To see all available sales opportunities you can type * in the Business Partner Code field and then press enter. Select whichever sales opportunity you want to close.
3) Click on the Summary tab of the sales opportunity you want to delete. Make sure it is set to OPEN.
4) In the Data menu along the top of the SAP B1 application, choose “Remove”. A message warning that this is irreversible will appear. To delete it, click continue.