Could not add a custom visualization as "display.visualizations.custom.type" is missing in ui-prefs.conf.

[reeta12345]

Could not add a custom visualization as "display.visualizations.custom.type" is missing in ui-prefs.conf.

[ssmoot_splunk]

This condition is caused by overriding the directive for display.visualizations.type as defined in ui-prefs.conf
The default value for this parameter is charting, if you set it to an invalid visualization type, you will get this error.
If you get the error, you can still select a viz type by hitting the Select... in the upper left hand corner of the visualization, selecting a viz type will add a directive in ...etc/users/-/app/ui-prefs.conf

Here is the spec for the parameter:
display.visualizations.type = [charting|singlevalue]

If you are unsure how to find out if you have an invalid viz type, use btool:
splunk cmd btool ui-prefs list --debug | grep display.visualizations.type

In my repro of the error, I used custom as a type, here is my btool:

root@so1:/opt/splunk# ./bin/splunk cmd btool ui-prefs list --debug | grep display.visualizations.type
/opt/splunk/etc/system/default/ui-prefs.conf display.visualizations.type = charting
/opt/splunk/etc/system/default/ui-prefs.conf display.visualizations.type = charting
/opt/splunk/etc/system/local/ui-prefs.conf display.visualizations.type = custom

To resolve, simply comment out the offending stanza:

#display.visualizations.type = custom

[niketn]

@reeta12345 which stanza is throwing above error? Do you know which Custom Visualization is this for? Also which version of Splunk are you using?

Kindly add more information for the community to assist you better.