When trying to run or execute a query select statement in the Editor window, even a simple select query, Toad gives the following error:
Object reference not set to an instance of an object.
This is an issue for any query, but this error may not occur if running the queries through the Query Builder.
Corruption in the editor.xml file.
1. Close out of Toad
2. Go to C:\Users\<YOUR_USER>\AppData\Roaming\Quest Software\Toad Data Point X.x\Layouts (where X.x is the version number)
3. Rename the file Editor.xml (i.e. Editor.xml_OLD) to reset the setting for the Editor window to default.
4. Restart and test the issue in Toad.
Per one user report, setting the "Show Script Results" option in the SQL Editor to true resolves the error.