Hi Naomi,
I found the issue: the file was named ZipX... but the designer.cs had the TableAdapter class specified as: ZIPX...
Very frustrating, but all sorted now. Thanks for jumping in.

>Hi,
>
>Did you forget to specify the base class on this line
>
>public partial class ZipXClientChargesTableAdapter ???
>
>What is this class is based on (or which interface it should implement)?
>
>>No one able to spot my probably simple mistake? :(
>>
>>>Hi,
>>>
>>>
>>>I have done this before on other table adapters successfully but for some reason it is not working on this one and I am not seeing what is causing it.
>>>
>>>I have some code to load data for a report that is timing out so I want to increase the timeout value, like this:
>>>
>>>

xxx.DataSets.ZipXClientChargesTableAdapters.ZIPXClientChargesTableAdapter
>>>                    zipXClientChargesTableAdapter = new xxx.DataSets.ZipXClientChargesTableAdapters.ZIPXClientChargesTableAdapter();
>>>zipXClientChargesTableAdapter.ClearBeforeFill = true;
>>>zipXClientChargesTableAdapter.SelectCommandTimeout = 300;

>>>
>>>This gives the error:
>>>
>>>xxx.DataSets.ZipXClientChargesTableAdapters.ZIPXClientChargesTableAdapter' does not contain a definition for 'SelectCommandTimeout' and no extension method 'SelectCommandTimeout' accepting a first argument of type 'xxx.DataSets.ZipXClientChargesTableAdapters.ZIPXClientChargesTableAdapter' could be found (are you missing a using directive or an assembly reference?)
>>>
>>>I have created a file called ZipXClientChargesTableAdapter.cs and placed it in the DataSets folder where the existing ZipXClientCharges.xsd is. This is the code in that file:
>>>
>>>

using System;
>>>using System.Collections.Generic;
>>>using System.Linq;
>>>using System.Text;
>>>
>>>
>>>namespace xxx.DataSets.ZipXClientChargesTableAdapters
>>>{
>>>    public partial class ZipXClientChargesTableAdapter
>>>    {
>>>        public int SelectCommandTimeout
>>>        {
>>>            get
>>>            {
>>>                return this.CommandCollection[0].CommandTimeout;
>>>            }
>>>            set
>>>            {
>>>                this.CommandCollection[0].CommandTimeout = value;
>>>            }
>>>        }
>>>
>>>    }
>>>}

>>>
>>>On the references to this.CommandCollection[0].CommandTimeout, I get an error:
>>>
>>>'xxx.DataSets.ZipXClientChargesTableAdapters.ZipXClientChargesTableAdapter' does not contain a definition for 'CommandCollection' and no extension method 'CommandCollection' accepting a first argument of type 'xxx.DataSets.ZipXClientChargesTableAdapters.ZipXClientChargesTableAdapter' could be found (are you missing a using directive or an assembly reference?)
>>>
>>>Which probably is the underlying issue.
>>>
>>>So, what am I missing?