I have a three columns in excel with data such as

```
section1     section2     section3     
 no             no          er3       
 er1            no          er3    
 no             no          no

```

how to write macros to Combine the data in the on column such as:

```
section_error    
    er3        
    er1,er3        
    no

```

So if there are only "no" then it should be once "no"
if there is something else besides "no", like "er1"or "er3" then only list of others signs. 
it is not exactly to join or to CONCATENATE (