excel - Differences between string representations of date/times -

In Excel 2007, I want the difference for the following string date / time:

  ABC1 Date 1 Date 2 A and B2 Difference 2009.11.28 01: 25: 46: 0287 2009.11.28 01: 25: 46: 0287? 3 2009.11.28 01: 25: 46: 0443 2009.11.28 01: 25: 46: 0443?  

I want to change the strings in date / time and then change the result as the difference of the two converted date / time.

  = subtit (left) (A2, 10), "post-less" itemprop = "text"> 
. "," / ") + Middle (A2128) + right (A2,4) / 86400000- (substitute ( Left (B2,10), ".", "/") + Middle (B2, 12, 8) + Wright (B4) / 86400000)  

By special request and Very Short Abbreviation:

  = Subtitle (left (A2, 10)), + REPLACE (rights (A2.13), 9.1,) "." - (Substituted ( Left (B2,10) "." ".", "/") + REPLACE (correct (B2, 13), 9,1, "."))  

< / Html >