Cannot open an encrypted partition

Hi,

Encrypted one of my partitions with Disk Encryption using a USB stick for authentication. Rebooted the machine the partition does not appear in the drive window, when I try to add the partition I receive an error informing me "cannot added encrypted partition, make sure the drive was a cde partition and the encrypted settings and password are correct.

As I used the wizards to perform the above task I assume the settings and thepasword are correct.
I have noticed on the lower left panel theere is a message informing me that there is a problem with the encryption subsystem.

Can you help
NightRider

your antivirus is preventing the cde service from starting…turn off boot sector scanning.

Louhbo