I am trying to replace all the occurrences of two spaces between a period and the start of the next sentence into one space. I looked around and in theory, in the Find and Replace dialog and using the "Find What" field, enter a space and then {2,}
Then I want to put one space in the field of what to replace this with. Somehow I haven't gotten this correct because the find command does nothing.

How can I accomplish this? Thanks.

You have to enable "Use Wildcards" for the {2} to work.
Although you may simply want to type two spaces in the Find box, and one space in the Replace box. That usually works for me.

You can do this with a wildcard Find/Replace, where:
Find = .{2,}
Replace = .^32

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]