In the createscript of the oppo_targetclose on the workflow screen (not the OpportunityDetailBox) you will do something like this:

if(CRM.GetContextInfo('oppo_mycheckboxfield') != 'Y')
  ReadOnly = true;

Thanks Vega, but it can't work like this as the field comes uncheked by default so putting this in the createscript of the checkbox fields always result at setting it readonly :)

Then the requirements aren't correct. If the value is not checked, the target close field is readonly, which is what the script does. If the value is checked, it will fail the condition and won't apply the read only attribute. You only want the user to be able to set the target close date when the checkbox has been ticked.

Then the requirements aren't correct. If the value is not checked, the target close field is readonly, which is what the script does. If the value is checked, it will fail the condition and won't apply the read only attribute. You only want the user to be able to set the target close date when the checkbox has been ticked.

1. This script must apply in the first workflow rule (the "new opportunity" one)

2. When I check, the target close is not readonly and can be edited

3. When I uncheck, the target close becomes readonly

4. and so on... So it should be dynamic, not static once for all !