One way I can think of is to use a conversion utility program (eg: 2dos) to convert the file format from unix to dos before doing the extraction.

Or try...

update aTable set bField=-1 where aField='aValue' and bField is NULL

One option is to set a default value to that particular column.

You can use xp_cmdshell and delete the file using dos command.

Change the delimiter to something that will not occure in ur data (|, ~ etc). I dont think you can enclose a varchar field with double quotes and even if...

Can u show ur format file once?