Login to the application as SYSADMIN
Responsibility : System Administrator
Profiles
System
Choose from the menu:
Help
Diagnostics
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Personalize
Create a new Rule
Seq : 10
Description : MO: Operating Unit
Level : Function
Enabled : [checked]
Specify the following Condition:
Trigger Event : WHEN-VALIDATE-RECORD
Trigger Object : PROFILE_VALUES
Condition :


Processing Mode : Not in Enter-Query Mode
Assign the following Actions to the Rule:
Seq : 10
Type : Message
Description : MO: Operating Unit
Language : All
Enabled : [checked]
Message Type : Error
Message Text : You must specify a profile option value at Site level for the profile option 'MO: Operating Unit'.
Save the changes
Close the System Profile Values form
Result
An error message will appear if an end user or a System Administrator now tries to remove the profile option value. The application will no longer allow anyone to delete the value and this breaks the environment however it will still be possible to specify a different organization at Site level.
Source
Metalink.oracle.com