Hi Guriqubal,

Monitor and keyborad connection is not supported with ACS appliance. For console connection, please follow the steps for serial connection.

Error:-     During startup, the ACS SE receives the At least one       service or driver failed during startup. use event viewer to examine the event       log for details error message.

Solution:-     This error on the ACS SE does not affect any of the ACS       functionalities. It is a       Microsoft Windows       error. This error appears because the monitor, mouse and keyboard cannot       be used on the appliance and are disabled by default.

The ACS appliance is a hardened, locked-down system and is designed       with security in mind. The appliance uses windows strengthen image, which has       all redundant services and connections stopped. It is made       to keep all viruses, worms, and DDOS attackers out. Hence there is no VNC, DOS       prompt, or any other way to reach the windows configuration. Services like the       mouse, keyboard and monitor are closed.

On rare occasions, it indicates that something is corrupted on the       appliance image. If you re-image the appliance, it fixes the issue in the       majority of instances. You can try to re-image the ACS as well.

http://www.cisco.com/univercd/cc/td/doc/product/access/acs_soft/csacsapp/install/instalap.htm#17544

and you can aslo check Installing and Configuring the Cisco Secure ACS Appliance:-

http://www.cisco.com/univercd/cc/td/doc/product/access/acs_soft/csacsapp/install/instalap.htm#wp1007555

thanks,

Vinay