Removing a string (located within one field) from the contents of another string within another field

What is the most straight forward method of removing a string (located within one field) from the contents of another string within another field?? Example: [FIELD1] ="klmnop" [FIELD2]="blah blah blah klmnop blah blah blah" End result for FIELD2 should be: "blah blah blah blah blah blah" This email message and all attachments transmitted herewith are trade secret and/or confidential information intended only for the viewing and use of addressee. If the reader of this message is not the intended recipient, you are hereby notified that any review, use, communication, dissemination, distribution or copying of this communication is prohibited. If you have received this communication is error, please notify the sender immediately by telephone or electronic mail, and delete this message and all copies and backups thereof. Thank you for your cooperation.