dont open it directly with excel use the get external data from the data tab
choose from text
find your text file click import
when the wizard pops up
make sure delimited is checked
click next
click next again
click first field
use ctrl+shift click last field to select all fields
under column data format
check the text box
all fields should now say text instead of general
click finish
in the window that pops up choose where you want it to start import to (usually =$A$1 of existing worksheet
click ok