Main Menu

Cannot open blob archive file: CMultiFieldBlob(mem-mapped file): Failed to open file

When I run Steam or try to connect to a Server I encounter this error:

Steam.exe (main exception): Cannot open blob archive file: CMultiFieldBlob(mem-mapped file): Failed to open file.

Please see the ClientRegistry.blob topic to troubleshoot this issue.

If renaming the ClientRegistry.blob file does not resolve the error and "SteamIDGetEncryptedUserIDTicket() failed with error1: cannot open blob archive file: CMultiFieldBlob(mem-mapped file): Failed to open file" appears in your game console when you attempt to connect to a server, further troubleshooting will be required.

Change Security Settings for Steam

 

Windows XP

Note: you must be logged in as an administrator to perform this task.

  1. Open Windows Explorer and go to Tools > Folder Options > View.
  2. Scroll to the bottom of the list and make sure that Use simple file sharing is unchecked.
  3. Click on the Apply button.
  4. Navigate to your the folder holding your Steam installation. By default, this is c:\Program files.
  5. Right-click on the Steam folder.
  6. Select Sharing and Security.
  7. Click on the Security tab.
  8. Grant all users full control of the Steam folder, files, and subfolders.
  9. Restart Steam and test.

 

Windows Vista

Note: you must be logged in as an administrator to perform this task.

  1. Navigate to your the folder holding your Steam installation.
  2. Right-click on the Steam folder.
  3. Select Sharing and Security.
  4. Click on the Security tab.
  5. Grant all users full control of the Steam folder, files, and subfolders.
  6. Restart Steam and test.

 

Operating System Issue

If the above instructions fail to resolve your issue, you should reformat your hard drive, reinstall your operating system, and reinstall Steam to resolve the issue.

Note: Using any portion of your old files might very well cause this problem to happen again.

 

Problem with Steam?

Contact Steam Support
Related Articles
Cannot open blob archive file: CMultiFieldBlob(mem-mapped file): Failed to open file ClientRegistry.blob
Cannot open blob archive file: CMultiFieldBlob(mem-mapped file): Failed to open file Steam.exe (main exception): CMultiFieldBlob(pSerialized)