If you encounter the error message “The link you follow has expired” during plugin installation process, you will need to increase some PHP variables.
This happens because projectopia.zip files size is larger than your PHP variable upload_max_filesize. You will have to increase your upload_max_filesize to a value larger than your projectopia.zip files size. As more features are added to the plugin, the file size will increase over time. Therefore, you may need to make adjustments when you install a new version.
In this case you can do the following.
Edit your .htaccess file and add in the following at the end of your file.
php_value upload_max_filesize 200M
php_value post_max_size 200M
php_value max_execution_time 1000
php_value max_input_time 1000
You should be able to upload install now
If not, please contact your web hosting company for help or install via FTP