Callback Technologies - Knowledge Base

CBFS Connect Articles

• What's New in CBFS Connect 2020

  CBFS Connect 2020 Upgrades and Migration Guide

• Getting Started with CBFS Connect

  The article shows how to get started with CBFS Connect step by step.

• Getting Started with CBFS FUSE

  The article shows how to get started with CBFS FUSE step by step.

• How can I make a file read-only for a certain process?

  First, you'll need to enable the FireAllOpenCloseEvents property. Then, anytime the CreateFile or OpenFile event fires, determine if the request ori ...

• How do I create a drive for only one user (session)?

  How to create a drive for only one user (session)

• How do I show different files to different users on the same filesystem?

  Showing different files to different users on the same filesystem

• How can I make my drive support paths longer than 260 characters?

  Making a drive support paths longer than 260 characters

• What is this strange file name with a colon inside?

  When handling the CreateFile , OpenFile , or other events, you may sometimes see filenames that contain a colon ( : ). This means that a request is ...

• What happens if the filesystem fails to delete the actual file from backend storage?

  Virtual filesystems created by CBFS Connect are no different than other filesystems in how such situations are handled: information about existence ...

• What effects does setting FileSystemName to NTFS have?

  What happens if a virtual filesystem

• Will the CBFS component fire multiple events for the same file at the same time?

  Discusses event firing behavior with regards to parallel request processing.

• Does the driver need to be reinstalled each time the computer reboots?

  How often the driver needs to be reinstalled.

• Can you provide a WHQL-certified version of the driver?

  Unfortunately, it is not possible for us to provide WHQL-certified versions of our products' system drivers for technical reasons. WHQL certificatio ...

• How do I collect a log of file operations on the drive for debugging purposes?

  How to collect a log of file operations on the drive.

• How do I notify the system that a file in a CBFS Connect drive

  How to notify the OS and CBFS Connect that a file in the virtual drive

• What is the sequence of events fired when Windows Explorer opens a directory?

  Describes the sequence of events fired when Windows Explorer opens a directory.

• I created a local mounting point with the STGMP_LOCAL and STGMP_NETWORK flags. Why is this drive visible in Windows Explorer's "Network" area?

  Discusses why a local network mounting point is visible in Windows Explorer' "Network" area.

• Can I clear the metadata cache?

  To clear the metadata cache for an individual file or directory, use the NotifyDirectoryChange method. To clear it for the entire virtual drive, dis ...

• Should I delete backend data in the CanFileBeDeleted event handler?

  No; the CanFileBeDeleted event handler is only used to check whether or not a file can be deleted. There's no guarantee that the file actually will ...

• Why doesn't returning error in the DeleteFile event handler prevent file deletion?

  This is the correct behavior. Windows can delete a file or directory in two ways: The first way: The file is opened. The "delete on close" flag is s ...

• Windows Explorer stops showing SMB shares after a network mounting point with a share is created.

  Troubleshooting why Windows Explorer stops showning SMB shares after a network mounting point with a share is created.

• How do I get rid of the Windows warning box when installing drivers?

  Getting rid of the Windows warning box when installing drivers

• When SerializeEvents is false, do filesystem operations for the same file fire on one thread?

  All filesystem operations for the same file will indeed fire on one thread (i.e., are serialized), but this thread is not always the same. The threa ...

• When I set "SectorSize" to 4096 and "StorageType" to "STGT_DISK_PNP", some applications can't access the disk. Why?

  In PnP mode, the OS builds a stack of drivers on top of the CBFS Connect virtual disk driver (the one that is presented in PnP mode). The CBFS Conne ...

• Why does the system become slow if I perform lengthy operations in the OpenFile, CreateFile, or CloseFile events?

  CBFS Connect processes requests in several threads in parallel to allow you to achieve optimal performance. However, the creation and closing of the ...

• Why can't I share a directory on my virtual drive?

  If a global mounting point has been added for the drive, directories can be shared. It is only when directories on drives mounted using a local moun ...

• Why is a timeout necessary?

  The timeout mechanism was implemented to avoid possible deadlocks in the system. These deadlocks can occur because of complications among the intera ...

• Is there a problem if timeout is disabled?

  Usually there isn't. But, there can be some unexpected long waits in the event handlers you implemented, and some influence from third-party system ...

• The Initialize method throws a strange exception saying that the driver is not found. Why?

  Why the Initialize method throws the exception "A volume has been accessed for which a filesystem driver is required that has not yet been loaded"

• Why can't I create a directory or file whose name ends with a dot (".")?

  This due to how Windows Explorer works, and the behavior is consistent with other filesystems. With Windows API functions, you can create and manage ...

• Windows 10 now supports long file names. Can we?

  CBFS Connect, as well as Windows, have supported long file names for years. The problem is that some applications have a hard-coded maximum length f ...

• If I grant a specific process access to the drive, will any child processes it creates be able to access the drive as well?

  Discusses whether child processes can access your application

• Why does Windows Explorer read files when I just browse a directory?

  The reason why Windows Explorer reads files when you are browsing a directory.

• Why isn't my mounting point visible in Windows Explorer?

  Discusses reasons why a mounting point may not show up in Windows Explorer.

• Why is copying files to/from a CBFS Connect drive so slow?

  Discusses why it takes longer to copy files to/from CBFS Connect drives compared to normal drives.

• Why doesn't CBFS Connect provide asynchronous versions of events?

  Discusses the reason CBFS Connect doesn't have asynchronous events.

• How do I make a Recycle Bin on my virtual drive?

  How to have a Recycle Bin on a virtual drive.

• Minifilter and legacy filter usage in CBFS Connect

  Information about use of minifilters and legacy filters

• Why is OnCloseFile event fired long after the file is actually closed?

  The reasons why you can observe delayed closing of a file