‘Attempting to Validate BBT Refcounts’ Outlook PST Error

Microsoft Outlook PST is the single file consisting of all email messages, notes, journals, tasks, appointments and other Outlook objects. This file is prone to corruption due to reasons like virus attack, saving PST on network, application faults, unexpected shutdown and other similar reasons. Thus for complete file restoration, you need to use your recent file backup. But in case you observe that backup is giving errors or is not updated to restore required data, commercial Outlook PST Repair tools can prove as valid tools to be used.

You might receive the similar error message while using Microsoft Office Outlook Inbox Repair Tool:

“Attempting to validate BBT refcounts”

“Couldn’t find BBT entry in the RBT (211C8)”

You receive such errors in the log report.


Possible causes for the above error to occur are:

  • PST file is large in size
  • Outlook is unable to find the BBT entry of the file
  • PST is damaged or corrupted

Note: Outlook 2002 and earlier versions have default file size limit of 2 GB. If PST grows beyond this file size limit, Outlook shows strange behavior and PST gets odds to corrupt. In Outlook 2003 and 2007, this file size limit has extended to default value of 20 GB.


To fix these issues, you should try performing these steps:

  • Try to reduce file size. You can empty the ‘Deleted Items’ folder and delete unimportant email messages from all folders including Inbox, Sent Items etc.
  • Try reinstalling Microsoft Office Outlook to resolve BBT errors
  • If PST corruption is the issue, you need to repair it. Since Inbox Repair Tool cannot repair such files, you should Repair PST using commercial applications.

Outlook PST Repair software are safe and advanced applications to repair damaged PST. These software deploy high-end scanning algorithms to examine a damaged PST file and repair it, without changing file original view and content. You can use these tools to Repair Outlook PST in any case of personal storage file corruption. They come equipped with self-descriptive interface, read-only design and automated recovery options.

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