I have changed my permalink to the custom structure /news/%postname% however I am now trying to set up a 301 redirect so if someone types in the old url of http://example.com/this-is-my-post they will automatically be redirect to http://example.com/news/this-is-my-post
I have successfully set up a redirect for my custom post types as I moved all the posts over from the custom post type "events" to "latest" by using this:
RewriteRule ^events/(.*) http://www.example.com/latest/$1 [R=301,L]
However I'm not sure I can use this to redirect the main blog posts without affecting the website pages.
To omit the requests for events or latest, you must define an appropriate condition. The rule looks similar to the one you already have
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_URI} !^/events/
RewriteCond %{REQUEST_URI} !^/latest/
RewriteCond %{REQUEST_URI} !^/news/
RewriteRule ^(.*)$ /news/$1 [R,L]
You may also combine the three excluding conditions into one
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_URI} !^/(events|latest|news)/
RewriteRule ^(.*)$ /news/$1 [R,L]
When everything works as it should, you may replace R with R=301 (permanent redirect). Never test with R=301.