When I retrieve a column of dates from a web query into Excel, it
returns the following:

2007-02-16 15:31:26
2007-02-16 15:39:18
2007-02-16 15:49:42
2007-02-16 15:40:02
2007-02-16 16:00:03

No matter how I try to format it, it refuses to accept the date
formatting. Tried formatting the cell. Tried paste special -
format. By accident, I hit F2 to edit the cell, and simply hitting
Enter, the date format changes to

2/16/2007 15:19

When I accidentally activated the cell, Excel recognized it as a date
and turned it into something useful. So, what is going on - and what
can I do to convert these seemingly nonsensical dates into a format
Excel recognizes as a date?