I was trying to test a web service ... facing error while selecting the service

This indicates that the application server was stopped when this data type was being created. The "IMPORTING" flag is currently on for this data type and should clear after 2 hours. I suggest you try again after that period of time.

Thanks Eduardo ... But I tried the same on cloud instance and local instance ..same error pops up .. when i change service interface and re-loads the service into Appian instance ... i tried even after 24 hours and even re-started my local .. but no luck ..

I tried to manually loads the web service CDT ,, see attached error ..
Please suggest !

Why are you importing the XSDs? You don't have to, they are created automatically by the Call Web Service node.

Yes.. they should be but they are not getting created .. see attached screenshot
So i tried to do the reverse .. thinking it will solve the problem but same error

We can confirm the issue is the IMPORTING flag if you are able to change the name of the CDT in the WSDL, you will see that at least this data type will not error out any more.

What version of Appian is this by the way?

Eduardo the service wsdl comes from 3rd party, I can't change CDT/XSD type name in WSDL, ,,,,, Appian Version is 7.4 and tested even on 7.5.. .
Some where Appian is storing the older reference, how can i identify where the reference is coming from ..

There's a cache for the WSLD and one for the data types.

A) If you think Appian is pulling out the old definition of the WSDL then the steps to perform are:

1. Delete the CDTs related to the Web Service. Make sure you delete all of them. Ideally you should sort by namespace to make sure you delete all of them.

It is very common for people to miss one or two making these steps fail

2. Open up the process model, right click on the Call Web Service Smart Service - Properties - Setup
3. Temporarily check Authentication Required and typed something in username and password and click Refresh
4. Uncheck the authentication required option.
5. Finish configuring the smart service.
6. Save and publish the model
7. Try again.

B) If the issue is the data types cache, again, this will be cleared after two hours, so I suggest you follow the step #1, restart your app server, wait two hours then try steps 2 to 7

Eduardo .. i tried all the steps ... but no luck .. all web service CDT's were deleted too.

Even restarted my local instance but same error results .. appian somewhere is referencing to few cdt's which are of enum type

Why do you say it's referencing those CDTs? do you mean the DataTransferObjects?