When trying to change connection point text on the Modify Connection Point Text dialog for a symbol on a project page, a "Some connection point text is invalid" message is displayed.
Connection point text is dictated by the assigned device family, if present. Connection point text used on the inserted symbol cannot violate what is assigned in the family. It is possible to "swap" connection point text with the text of another connection point on the symbol as long as the family specifies that connection point text for the symbol.
If the family specifies null/blank connection point text, the user can specify any connection point text when placing the symbol. An exception to "any connection point text" would be the use of special characters. Use only letters and numbers to avoid problems.
Assign the family that contains the desired connection point text to the device. This may require modifying the family to suit or creating a new family. Alternates can be added to families so different connection point texts and/or a different symbols can be specified for a given role in the family. Use Create Family to create or modify device families. After modifying the family assigned to the device, be sure to use Update Family to bring the modified family definition into the project(s).
If a device family is being used for purposes other than specifying connection point text, create the family with no connection point text specified. Use Create Family to create or modify device families. The user will have to enter any desired connection point text when inserting symbols for the device.