If you get the Are You Sure You Want To Do This? message after uploading the theme's zip file via Appearance / Themes menu in your WordPress, it means that your server has low upload limits.
You may go around this problem in two ways:
- Install the theme using an FTP client like FileZilla. The process is described in the Installing Theme article.
- Increase the upload limits on your server, described below.
Below are the recommended values for specific options in your server configuration:
- memory_limit 128M
- post_max_size 64M
- upload_max_filesize 64M
- max_execution_time 60
If you are not familiar how to change those values in your php.ini file then please contact your host/server provider about it. They should change them in an instant.