First of all: your host created this issue so they're the ones to solve it.
You could check file permissions. Any FTP program should have this ability. See if there's anything awkward with the admin.php file in the root of your blog. File permission should typically be 664 or

"-rw-rw-r--" would be represented as 664 in three-digit octal.

When i change admin.php file permission from 644 to 664 have error.

"Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, webmaster@blogtika.com and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request."

for ""-rw-rw-r--" would be represented as 664 in three-digit octal." It is?

Hi Managerview,

Try 666 which makes it world writable and is a masive security hole so you should change it back as soon as you have saved (succeed or fail)

The reason why this can be necessary is that there are two main ways of running php, either "native" as the web servers user & group (often apache:apache) or via suPHP as the script owner's user & group. The problem you're having can be caused by running native.

HTH

Bruce

PHP needs the "x" setting to run. Ask your host if they're running mod_security

¥