With the release of wordpress 2.8 there was an error while installing some plugins on the wordpress from admin panel. This error was not fixed till wp 2.8.1
When the admin tries to install the plugi, it gives the following error:
Installing Plugin: —————–
Downloading install package from http://———————-.com
Unpacking the package.
Incompatible archive PCLZIP_ERR_BAD_FORMAT (-10) : Invalid archive structure
The error can be solved by downloading this new http.php file from official WordPress site and over writing it on your current file (make sure to backup your current http.php file).
https://core.trac.wordpress.org/export/11450/trunk/wp-includes/http.php
Hope it solves the issue.
Please note, if you have recently upgraded your wordpress and are getting this issue (if you have solved it last time) make sure that you have replaced the http.php file in your wordpress with the above file again.
Update: Stacy commented:
Hey guys, I found out that this error is also caused by a full directory in cpanel. Make sure you have enough disk space :) good luck !
Hopefully this will solve the issue with wordpress sayingIncompatible archive pclzip_err_bad_format (-10) : Invalid archive structure