BleepingComputer.com: De-crypt a folder

I encrypted a folder using EFS (right-clicked, Encrypt) but now I can't un-encrypt the folder. When I right click on Properties and uncheck Encrypt, nothing happens. I know the password but I don't know how to get a box to come up where I can enter it. This happened when I reinstalled Vista, even though the encrypted folder was on an external hard drive.

I know there is a program that can help with this but it costs $150.00. Can anyone suggest an alternative?

Thanks.

EFS folders are encrypted using certificates and keys linked to a username, you do not have to enter a password. If you move the files, you will also need to move the encryption certificate or you will be unable to decrypt the file. Decryption is not impossible, you could try copying the file over to a FAT32 disk since the NTFS encryption is removed automatically. EFS only works on NTFS drives, moving it to a FAT32 drive might work. But the OS might prevent this or corrupt the data. You could also try a program that decrypts the data. I use EFS from time to time and all I have to do is just double-click on the folder as though I'm opening it. If there is no key to open the folder and files, then access is denied.

Thanks. I must have lost the keys when I re-installed Vista.