Your cells are formatted as text. This can be fixed by following these directions.

 

Select one column at a time by clicking the column letter (for example, click A to select Column A)

Choose Data,  Text to Columns - a wizard will start

Make sure Delimited is checked on the first screen of the wizard

Click the Next button.

Place a check in Other (remove any other checked boxes)

Click the Next button

Place a check in General

Click Finish

Repeat for each column that contains data.

 

Press CTRL-A to select the entire worksheet.

Choose Edit, Clear, Formats

 

Place your insertion point at the first cell below a list and click the AutoSum button

Press Enter to accept the range.

You'll see the sum.

In great anticipation, I did meticulously all you said...ALAS same old error msg at the end! No sum regards thanks all yr advice ferkel

I've sent you the fixed file via email. Please let me know if you have a problem with it.

 

I noticed you had some cells unlocked. Was there a reason for this?