WordPress Help - Seo Pressor error

Hello, I've installed Seo pressor, but when I try to start it it says - The plugin generated 7 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.

And when I want to write my post it says - Warning: Cannot modify header information - headers already sent by (output started at /home/abexerci/domains/abexercisesformenv.com/public_html/wp-content/plugins/seo-pressor/seo-pressor.php:45) in /home/a4fs654/domains/4fasas45sa.com/public_html/wp-includes/class-wp-ajax-response.php on line 129

When i update my post it says - Warning: Cannot modify header information - headers already sent by (output started at /home/abexerci/domains/abexercisesformenv.com/public_html/wp-content/plugins/seo-pressor/seo-pressor.php:45) in /home/eqwwf/domains/afqwqwfqwf/public_html/wp-includes/pluggable.php on line 897


I found a solution to delete white blacks at the end and start, but when I start to upload my fixed plugin it says -
Unpacking the package…
Incompatible Archive. PCLZIP_ERR_BAD_FORMAT (-10) : Unable to find End of Central Dir Record signature






Please someone help me, I've tried it with Dreamwiever MX 2004, but it won't help.



Please download the file - Hotfile.com: One click file hosting: seo-pressor.php and correct it, I don't know what to do


Thank you for your time,



Laurynas