When we adding service reference to project sometimes we encounter “object reference is not set to an instance object” error. Sometimes it fix after follow following steps.
Step 1: Check are there any errors in WCF service and if there were errors fix it and retry.
Step 2: If there were existing service reference then delete it and add again.
Step 3: If step 2 not success then delete reference from service reference folder in project location (from hard disc) and try to add reference again.
Step 4: If first three steps not working go to the app config or web config file and remove relevant endpoint settings and try to add again.
Step 5: Host WCF service in iis and add service reference from iis url
