How to block attachments in a Outlook

How to block attachments in a non-Exchange environment

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

Use the information that is in this section if you are running Outlook in a non-Exchange environment and you want to block more attachment file name extensions than those that Outlook already blocks.

If you are using Outlook 2000, Microsoft Office 2000 Service Pack 3 (SP3) or later must be installed on your computer so that you can configure Outlook 2000 to block certain attachment file name extensions.

To obtain the latest service pack for Microsoft Office 2000, click the following article number to view the article in the Microsoft Knowledge Base:

If you are using Outlook 2002, Microsoft Office XP Service Pack 1 (SP1) or later must be installed on your computer so that you can configure Outlook 2002 to block certain attachment file name extensions. To obtain the latest service pack for Microsoft Office XP, click the following article number to view the article in the Microsoft Knowledge Base:

Outlook uses the Level1Add registry key to permit you to add additional attachment file name extensions types that you want to block.

To add additional attachment file name extensions types that you want to block, you must add the Level1Add key to the registry. To do this, follow these steps.

For Outlook 2000

Follow these steps, and then quit Registry Editor:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following key in the registry:
   HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Outlook\Security
3. On the Edit menu, point to New, and then click String Value.
4. Type Level1Add, and then press ENTER.
5. On the Edit menu, click Modify.
6. Type <file_name_extensions>, and then click OK.

Notefile_name_extensions is a list of the attachment file name extensions. Each attachment file name extension is separated by a semicolon. For example, type .zip; .gif if you want to block both .zip and .gif files from appearing in the e-mail message as an attachment.

Outlook 2002

Follow these steps, and then quit Registry Editor:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following key in the registry:
   HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Outlook\Security
3. On the Edit menu, point to New, and then click String Value.
4. Type Level1Add, and then press ENTER.
5. On the Edit menu, click Modify.
6. Type <file_name_extensions>, and then click OK.

Notefile_name_extensions is a list of the attachment file name extensions. Each attachment file name extension is separated by a semicolon. For example, type .zip; .gif if you want to block both .zip and .gif files from appearing in the e-mail message as an attachment.

If Outlook 2002 does not behave differently after you add the Level1Add registry value, click the following article number to view the article in the Microsoft Knowledge Base:

Additionally, you can add additional attachment file name extensions types that you want blocked by using system policies to add the following registry key for Outlook:

Outlook 2003

Follow these steps, and then quit Registry Editor:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following key in the registry:
   HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Security
3. On the Edit menu, point to New, and then click String Value.
4. Type Level1Add, and then press ENTER.
5. On the Edit menu, click Modify.
6. Type <file_name_extensions>, and then click OK.

Notefile_name_extensions is a list of the attachment file name extensions. Each attachment file name extension is separated by a semicolon. For example, type .zip; .gif if you want to block both .zip and .gif files from appearing in the e-mail message as an attachment.

Outlook 2007

Follow these steps, and then quit Registry Editor:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following key in the registry:
   HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Security
3. On the Edit menu, point to New, and then click String Value.
4. Type Level1Add, and then press ENTER.
5. On the Edit menu, click Modify.
6. Type <file_name_extensions>, and then click OK.

Notefile_name_extensions is a list of the attachment file name extensions. Each attachment file name extension is separated by a semicolon. For example, type .zip; .gif if you want to block both .zip and .gif files from appearing in the e-mail message as an attachment.

Outlook 2010

Follow these steps, and then quit Registry Editor:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following key in the registry:
   HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Security
3. On the Edit menu, point to New, and then click String Value.
4. Type Level1Add, and then press ENTER.
5. On the Edit menu, click Modify.
6. Type <file_name_extensions>, and then click OK.

Notefile_name_extensions is a list of the attachment file name extensions. Each attachment file name extension is separated by a semicolon. For example, type .zip; .gif if you want to block both .zip and .gif files from appearing in the e-mail message as an attachment.