On Sun, 15 Nov 2009 09:02:01 -0800, fruitchunk
wrote:

Sorry, I still have a few errors, I will give you actual data:
0017 GMT 8
0045 GMT 1
0256 GMT 11
0856 GMT 10
0902 GMT 13
0154 GMT 5.5
For the above I get #######, for all other records I get the correct answers.



Now with more information as to your requirements, try this:

=1+TEXT(A1,"00\:00")-(MID(B1,4,5)+5)/24

--ron