Hi @plamping 

There are 2 options here, the first would be the most appropriate but requires the most work to correct, second is more of a quick fix but would need to be done again if this scenario occurs again. 

The issue you have now is that you have essentially 2 versions of the forms available for that list, legacy that contains Choice A and B and New that contains B and C.

To handle this from a data level is the most important aspect as that determines how forms are displayed.

Option 1: You take your choices and place them as new items in a SharePoint list e.g.

Then on your form you convert the dropdown/radio choices into a lookup control pointed at your new list, you don't do this by replacing the choice field but instead you add the lookup in addition for now to retain the data.

This will have the same effect as you currently have issues with in terms of historical data so you will need to correct that, you can use a workflow to look the Sharepoint list items and correct the choices, changing A into 1 and B into 2 and C into 3, this is because lookups store IDs.

Once historical data is corrected to the new lookups you can then remove the standard dropdown/radio field.

The advantage of this is you can then use columns in the look up list to determine filters like active etc to decide if they show up in the dropdown or not, you can then add remove or modify the dropdown choices on the fly.

Alternatively option 2 you embrace the change in forms and make use of content types, this method could be more involved but would need you to enable content types on the list and have a 'legacy' form and a 'new' form, with that you can change which form is there as default when you click new, any existing forms will remain on the old form definition and choice controls.

This is really a good choice if you want to leave the legacy form as is and move somewhere different with the new form designer.

You could also mix these solutions together and perhaps on the old form show the choice field and new form has the lookup. 

Hope this helps.

Thank you for the replies, everyone. I ended up simply removing Option A in the Choice column.  The user said she could live with the downsides of it not displaying accurately on old forms.  Yes, I could have tried Jake’s Option 1 but perhaps down the road I might use it for something else.

Hi @plamping 

Here is my solution. (before you remove option A and add option C)

1. Add another SP column “Option_A_Ticked” - this column is a flag to indicated that Option A was previously selected but now its no longer available. Text or Yes/No type field will work.

2. You will need to “mark” the “Option_A_Ticked” column.
   Text field can use a “x” character. Yes/No field needs to be ticked. 
   You could do it manually or create a workflow - check if “Option A” was selected. If YES then “mark” the “Option_A_Ticked” column. 
   NOTE: the workflow will only work if the option A still exist. The workflow will fail to find option A should you have removed it. 
3. Update your form. 
   Create a new Label.
   Add a Rule to Show the Label when “Option_A_Ticked” column is enable 
   and to Hide the Label when “Option_A_Ticked” column is disable 

   

    

4. Older forms with option A selected will show the Label.
   Older forms will also show the newer option C (just add another label to inform users when that option was added)

Anyway, as @SimonMuntz said, there is not real way to resolve this issue. You will need to discuss with your Business Users and try to agree upon a solution. 

Thanks.

For some reason, I cannot mark any of the replies as the Solution. And why does it say my post is from 3 years ago?