ArcGIS Pro unique value renderer, Unable to Add New Value

[ahmed_hussiney]

I had created ArcGIS Pro project with one Map this map was imported from ArcMap MXD, The map contains multiple layer already symbolized using unique value renderer single or multiple fields, In both cases when I try to add new value to symbol classes using the following steps:

- Right click layer 

- Select symbology to open symbology pan

- The Symbology is already using "Unique value" method.

- Then click "add unlisted values" button.

- Then from options click "Add new value"

but rather than add new value and enter value and label it return the following message :

"Requested operation could not be completed"

Note : when I tried in a new Map with layer added and symbolized in ArcGIS pro I can add unlisted value that has no matching data record using "add new value" option.

So what could be the issue in my case, any suggestion ?

[DanPatterson]

version of Pro?

BUG-000130218: It is not possible to add unlisted values for Unique.. (esri.com)

and a workaround

[ahmed_hussiney]

Hi Dan,

Sorry for late response, My ArcGIS Pro version in 2.6.0 , I tried this steps on some layers and it work with no issue, So I don't think it is retired in this version of Pro, But some layers which I had imported from exist MXD is showing this issue and I can't get the root cause of this specially that other layers imported from same MXD is working.

[MatthewC]

@DanPatterson I just had this same issue in ArcGIS Pro v. 3.4.0.  I have symbology where I need to use an Expression to create a single concatenated value from four fields within the feature class so that I can symbolize various conductor types by status, overhead/underground, phase and type.  When I use unique values with the concatenate expression I'm unable to add the unique values to the classes list.  I tried the work around with no luck.

[SarahMorrison]

I am having this issue on a newly created feature class. I want to use the base symbology from another feature layer, but when I import the symbology and then attempt to add a new value I get the "Requested Operation could not be completed" message. If I try to add a new value BEFORE importing the symbology it works just fine, but I don't want to have to create all the other classes manually and am not sure WHY it won't let me do this.