I got this message on the plugins page when I activated this plugin:
The plugin generated 194 characters of unexpected output during activation. If you notice “headers already sent” messages, problems with syndication feeds or other issues, try deactivating or removing this plugin.
Also it threw the following errors into my php error log:
WordPress database error Specified key was too long; max key length is 1000 bytes for query CREATE TABLE wp_1_prtools_url (^M
ID int(11) NOT NULL AUTO_INCREMENT,^M
entrydate int(11) DEFAULT '0' NOT NULL,^M
lastupdate int(11) DEFAULT '0' NOT NULL,^M
url_type char(50) NOT NULL,^M
url VARCHAR(500) NOT NULL,^M
pr int(11) NOT NULL,^M
UNIQUE KEY id (id),^M
UNIQUE KEY url (url)^M
) made by activate_plugin, do_action, call_user_func_array, prtools_install, dbDelta
This is because my DB is set to UTF8 which uses 3 bytes per character which makes the url key 1500 bytes which exceeds the mysql limit.