[RCU] Blank Page when hitting roundcube and error in installer

Hi,

I installed roundcube 0.5.3 on a shared windows hosting plan about a month ago and it was working until 6 days ago.

Since then I am getting blank screen when hitting the URL that should point to the login screen. So the login screen is blank. No roundcube log is created within past 6 days and all log entries are older than 6 days. When I hit the installer URL I receive the following error:

Fatal error: Allowed memory size of 262144 bytes exhausted (tried to allocate 98304 bytes) in D:\sites\behbah\roundcube\program\include\main.inc on line 311

Connection with MySQL database and all user permissions are correct.

I am having hard time tracking down what can caused this. Any idea what can cause this?

Thanks,

Kasra