I think the OP meant the list of messages in the inbox or even the list of
messages in all message folder
that would be doable.
1. start while current view is inbox.
2. In the advanced toolbar-> the messages listbox,
select define view and then select the 2nd row for Messages -All mail and
post folders
3 click modify
4 click Other Settings
5 click Row Font and then select the font suitable size
ok...Apply View
font size for Outlook Message folders
for just the current view like the inbox, one would have selected the for
the current view only row instead of the 2nd row show above