Ok i had some spare time so i played around with this. this was a really simple fix that i could have given you in 5 minutes if you had explained step 1, etc. For future reference if you want a quick answer then provide a good question. ;) Thank you for reporting this issue.
Add this .htaccess code shown below in your wp-admin .htaccess file - NOT YOUR ROOT .htaccess file. And not all the code - just the portion of .htaccess code shown after # REQUEST METHODS FILTERED and before the start of the BPS security filters.
# REQUEST METHODS FILTERED
RewriteEngine On
RewriteCond %{REQUEST_METHOD} ^(HEAD|TRACE|DELETE|TRACK|DEBUG) [NC]
RewriteRule ^(.*)$ - [F,L]
# Allow wp-admin files that are called by plugins
# Fix for WP Press This
RewriteCond %{REQUEST_URI} (press-this\.php) [NC]
RewriteRule . - [S=1]
RewriteCond %{HTTP_USER_AGENT} (<|>|'|%0A|%0D|%27|%3C|%3E|%00) [NC,OR]
RewriteCond %{HTTP_USER_AGENT} (libwww-perl|wget|python|nikto|curl|scan|java|winhttp|HTTrack|clshttp|archiver|loader|email|harvest|extract|grab|miner) [NC,OR]
RewriteCond %{THE_REQUEST} \?\ HTTP/ [NC,OR]
RewriteCond %{THE_REQUEST} \/\*\ HTTP/ [NC,OR]
RewriteCond %{THE_REQUEST} etc/passwd [NC,OR]
RewriteCond %{THE_REQUEST} cgi-bin [NC,OR]
RewriteCond %{THE_REQUEST} (%0A|%0D) [NC,OR]
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Since there is a conflict with WP's Press This functionality and this is a safe thing to add as a standard to BPS, this code will be included as standard wp-admin .htaccess coding in the next release of BPS >>> BPS .46.9.