Unfortunately the last upgrade to Mylinks 4.6 broke my site for all URLs contianing a ? (probably similar problem as reported by mlauten in another topic).
All URLs containing "?" (e.g. logout) generate a dozen of errors like :
Warning: Cannot modify header information - headers already sent by (output started at /(...)/wp-content/plugins/mylinks2/mylinks.php:1) in /(...)/wp-login.php on line 368
I tried to open mylinks.php and options.php and save it with UTF-8 without BOM encoding (I remembered it helped with another similar error with another plugin), without success.
Test URL if you want to reproduce the error: -www.around-annapurna.com/wp-login.php?action=logout