How To Fix SWF_FLEX_DEF113 - Outcome ID '&' should consist of characters, digits and '_'

SAP Error Message - Details

• Message type: E = Error

• Message class: SWF_FLEX_DEF -

• Message number: 113

• Message text: Outcome ID '&' should consist of characters, digits and '_'

What causes this issue?

&V1& cannot be used as ID for an outcome. The ID must follow rules:
Not empty
Contains only characters, digits and '_'
Does not start with '_'

System Response

System does not allow to store the entity.

How to fix this error?

Please enter an ID which follows the rules defined above. Best Practice
for names are 'CamelCase' notation e.g.
stepExecuted
invoiceApproved

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.