I've "small" problem . I've got few website and some of the are infected by japanese seo keywords. When I change permission for .htaccess and index.php in main folder after this permission back to 444 and securitychecpro can't fix problems with .htaccess. These website is white blank. Have you any idea how to resolve this problem? Malwer scan found few files like about.php which I delete, but still I can't change permission these two file. Sorry for my english and please figure out this problem.
That usually happens because there is other security measures or the site is still infected. Joomla protects the configuration file with those permissions (444) but not those files.
Do the following:
Change those file permissions using ftp.
Be fully sure the malware scan is configured to analyze the entire filesystem, looking also for suspicious patterns (global configuration -> malware scan tab -> deep scan enabled and timeline set to anytime).
Send me an screenshot of malware found.
Set the file integrity scan to be launched every 2 hours. This way if any file is added or modified you will be alerted.
I think there is a script running that changes file content and permissions, probably put there by the hacker. But this should not be allowed by your server configuration.
I think you need the help of your hosting provider to check what's happening. The first step should be to check the server and after that gain access to the entire filesystem, delete malicious files and be fully sure the server is configured properly to avoid cases like this again.
Once done Securitycheck Pro will protect you; be sure that you don't have vulnerable extensions (check vulnerabilities option) and configure the cron to launch a file integrity every few hours. This way you will be alerted if any file is added or modified.