On a Windows Vista-based computer, when you use the Win32_EncryptableVolume Windows Management Instrumentation (WMI) class to check whether drives are encrypted or not, the floppy disk drive lights and the CD drive or DVD drive lights flash unexpectedly during the query process. This issue occurs even when you explicitly specify the drives to query.

Note: The Win32_EncryptableVolume WMI provider class represents an area of storage on a hard disk that can be protected by using BitLocker Drive Encryption. Only NTFS volumes can be encrypted.

After you upgrade a computer from Windows XP to Windows Vista, you cannot send or receive encrypted Microsoft Message Queuing, also known as MSMQ, 4.0 messages. The attempts to send or to receive encrypted Message Queuing messages fail. Additionally, you receive the following error message:

0×80090016 “The key container could not be opened”.

You use BitLocker Drive Encryption to encrypt non-operating-system volumes on a Windows Vista Service Pack 1 (SP1)-based computer. Then, you roll back Windows Vista SP1 to the release version of Windows Vista. In this situation, you may not have automatic access to the BitLocker-encrypted data volumes.

In Windows Vista, the Svchost.exe process stops responding when you try to copy encrypted Encrypting File System (EFS) files to a Web Distributed Authoring and Versioning (WebDAV) resource. If you use Windows Explorer to do this, Windows Explorer stops responding. You may have to restart the computer.

Note: The Svchost.exe process hosts the WebClient service.

When you try to save an encrypted 2007 Microsoft Office document to a WebDAV resource, you may receive an error message that says that the document cannot be saved.

You use the Back up files option in the Backup and Restore Center in Windows Vista. However, files are not backed up that are encrypted by using the Encrypting File System (EFS).

Note: The Back up computer option in Windows Vista correctly backs up and restores EFS-encrypted files.