>>>I have somehow managed to set a table to read only. How do I set it to read write, please.
>>
>>USE tablename EXCLUSIVE
>>
>>in case you need to edit the structure or ZAP it
>
>thanks but it did not solve the problem. 'Read only' remains in power

Is this table part of DBC?

If not and, suppose, you copy the files into another folder, is it still read-only? Did you check files properties in Windows Explorer?