How to improve performance by tuning content conversion in Enterprise Vault (EV) for Microsoft Exchange.

Problem

When using the Enterprise Vault User Extensions to view the contents of an archived item by simply opening the archived item from within Outlook, this displays the item in its associated application. For example, Microsoft Word documents are displayed using Microsoft Word.

This functionality depends on shortcuts to the archived items being left in the user's mailbox when items are archived. If this is not the case, use the Enterprise Vault Web Access application to search for items and view them in their associated application.
 
Archived items can only be displayed using their associated application if both the Enterprise Vault User Extensions and the software used to run the item's application are installed on the client machine. However, if this software is not installed, search for items using the Enterprise Vault Web Access application and view them in HTML format.

Note: As of EV 12 the conversion configuration settings are available in the advanced site settings.  Content conversion registry settings can be used to override site settings for particular EV servers.

Solution

To display archived items in HTML format using the Enterprise Vault Web Access application, the Storage Service converts the contents of archived items into HTML using a set of converters. If the items the Storage Service is trying to convert are quite large or complex, then there may be an impact on EV performance. To reduce this impact on performance, EV can be configured to modify the content conversion function.

Note: Changing any registry key value mentioned in this document requires the stopping and restarting of the Storage Service. Many of the settings below are now available in the Vault Administration Console within the Content Conversion section of the Site Properties > Advanced tab. 

Converting Excel and Word Documents to Text
 
Enterprise Vault converts Microsoft Excel and Microsoft Word documents to HTML. If EV performs large conversions or if the documents are complex, there may be performance problems. Performance can be significantly improved by making EV convert the documents to text instead of HTML.
 
Enterprise Vault provides two registry values that can be set to convert Word and Excel documents to text instead of HTML:

Warning: Incorrect use of the Windows registry editor may prevent the operating system from functioning properly. Great care should be taken when making changes to a Windows registry. Registry modifications should only be carried-out by persons experienced in the use of the registry editor application. It is recommended that a complete backup of the registry and workstation be made prior to making any registry changes.
 

1. To convert Excel documents to text instead of HTML, set the following registry key to 1:

Location: HKEY_LOCAL_MACHINE
                   \SOFTWARE
                         \Wow6432Node
                              \KVS
                                   \Enterprise Vault\

Name:     ConvertExcelToText
Content:  REG_DWORD
Values:    1 - Convert to text
               0 - (Default) Convert to HTML

2. To convert Word documents to text instead of HTML, set the following registry key to 1:

Location: HKEY_LOCAL_MACHINE
                   \SOFTWARE
                         \Wow6432Node
                              \KVS
                                   \Enterprise Vault\

Name:     ConvertWordToText
Content:  REG_DWORD
Values:    1 - Convert to text
               0 - (Default) Convert to HTML

Items staying in the Message Queues for a long time
 
One reason for items to stay on the Enterprise Vault Storage Archive queue for a long time is that they really are taking a long time to be converted. When they reach the maximum time for the conversion, the item is archived but there is no HTML version. The item is archived and a message is written to the Windows NT Event Log.
 
If many items are taking longer than the default 10 minutes allowed, change the timeout value.

1. To change the timeout, edit the following registry key:

Location: HKEY_LOCAL_MACHINE
                   \SOFTWARE
                         \Wow6432Node
                              \KVS
                                   \Enterprise Vault\

Name:    ConversionTimeout
Content:  REG_STRING
Values:    Integer type number representing the number of minutes before the timeout occurs.  The default value is 10 (minutes).

Excluding Items from Content Conversion
 
If some types of items are causing problems when they are being converted, they can be excluded from conversion. The item attributes are indexed in the usual way and the item is archived in its native format but not converted to HTML. The user will not be able to preview an item that has not had its content converted to HTML.

1. To exclude types of items from conversion, add the item's file extension to the following registry key:

Location: HKEY_LOCAL_MACHINE
                   \SOFTWARE
                         \Wow6432Node
                              \KVS
                                   \Enterprise Vault\

Name:     ExcludedFileTypesFromConversion
Content:  REG_STRING
Values:    .filetype[.filetype].
     For example, to exclude *.JPG and *.CAD files from conversion, set the key to:  .JPG.CAD

Note: If a specific file causes issues processing but all or most other files of the same type do not experience those issues then there may be an issue with the specific file. To investigate further the problematic sample must be provided to support for further investigation.
 

Prevent all Content Conversions
 
If items are taking a long time to convert and there is no need to view the HTML content of items from the EV Web Application or through OWA, disable content conversion for all items.

1. To disable content conversion for all items, set the following registry key to 1. To allow content conversions, set this to 0.

Location: HKEY_LOCAL_MACHINE
                   \SOFTWARE
                         \Wow6432Node
                              \KVS
                                   \Enterprise Vault\

Name:     BypassConversions
Content:  REG_DWORD
Values:    1 - Content conversions are not performed
               0 - (Default) Content conversions are performed

 
This improves archiving processing performance quite considerably as well as reducing the disk space requirements of archived items.