06/02/ · To enable this file type, do the following: Click the File tab. Under Help, click Options. Click Trust Center, and then click Trust Center Settings. In the Trust Center, 10/07/ · Over the years, MS has blocked more file types by default. You can turn them on simply by clicking in the check boxes. First you have to decide what the check marks will do. Click Options > Trust Center > Trust Center Settings, and then click External Content. Click the option that you want under Security settings for Linked Data Types: Enable all Linked Data 09/04/ · To restrict the formatting changes, follow the steps below. Select the Review Tab, then select Restrict Editing. Under Formatting Restrictions, select Settings. In the pop-up ... read more
The issue can also occur when you open an embedded or linked Office file in an Office application. For example, you have a Visio object embedded in a Word document. When you try to open the Visio object, you receive a similar error message in Word. To resolve this issue, you must change the File Block settings in the application that owns the blocked file type. In this example, you must change the File Block settings in Visio instead of in Word.
If the error message mentions Excel file type, go to Excel to change the File Block settings. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Table of contents Exit focus mode. Read in English Save Table of contents Read in English Save.
Table of contents. Note Clear the option means allow user to open or save the file. Note The File Block Settings can be controlled by a Group Policy Object GPO and are part of the recommended security base line settings. Plan and configure Trusted Locations settings for Office If you are a domain administrator, you can override the settings for file types that are blocked by using a Group Policy template.
This update provides updated Group Policy template files that you can use to override the settings for the files that are blocked by default or to block additional file types.
Note You can control the restrictions for the following file types by using the File Block Settings dialog box:. To restrict the kinds of files that you can open or save in Visio , an administrator can use the Office System Administrative Templates to configure the registry on the client computer. For more specific information about how to use settings to block users from opening and saving specific file formats in Office programs, see Overview of Group Policy for Office Skip to main content.
This browser is no longer supported. Download Microsoft Edge More info. Table of contents Exit focus mode. Read in English Save Table of contents Read in English Save. Table of contents. Important This section, method, or task contains steps that tell you how to modify the registry. Note If the issue occurs in an embedded or linked Visio file in other Microsoft Office applications, clear both the Save and Open check boxes for the "Visio Binary Drawings, Templates and Stencils" file type.
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To help protect your security and privacy, Microsoft Office is configured by default to block external content—such as images, linked media, hyperlinks, and data connections—in workbooks and presentations. Blocking external content helps to prevent Web beacons and other intrusive methods that hackers use to invade your privacy and lure you into running malicious code without your knowledge or consent.
External content is any content linked from the Internet or an intranet to a workbook or presentation. Some examples of external content are images, linked media, data connections, and templates. Hackers can use external content as Web beacons. Web beacons send back, or beacon, information from your computer to the server that hosts the external content. Types of Web beacons include the following:. Images A hacker sends a workbook or presentation for you to review that contains images.
When you open the file, the image is downloaded and information about the file is beaconed back to the external server. Images in Outlook e-mail messages Microsoft Office has its own mechanism for blocking external content in messages. This helps to protect against Web beacons that could otherwise capture your email address. For more information, see Block or unblock automatic picture downloads in email messages. Linked media A hacker sends you a presentation as an attachment in an email message.
The presentation contains a media object, such as a sound, that is linked to an external server. When you open the presentation in Microsoft PowerPoint, the media object is played and in turn executes code that runs a malicious script that harms your computer. Data connections A hacker creates a workbook and sends it to you as an attachment in an email message. The workbook contains code that pulls data from or pushes data to a database. The hacker does not have permissions to the database, but you do.
As a result, when you open the workbook in Microsoft Excel, the code executes and accesses the database by using your credentials.
Data can then be accessed or changed without your knowledge or consent. If there are external data connections present in your workbook or presentation, when you open the file a business bar notifies you that the external content has been disabled.
Click Enable Content on the business bar if you want to unblock the external content. To learn how to make a secure decision before clicking an option, see the next section.
When a security dialog box appears, you have the option to enable the external content or to leave it blocked. You should only enable the external content if you are sure that it is from a trustworthy source. Important: If you are sure that the external content in a workbook or presentation is trustworthy, and if you do not want to be notified about this specific external content again, instead of changing the default Trust Center settings to a less safe security level, it is better to move the file to a trusted location.
Files in trusted locations are allowed to run without being checked by the Trust Center security system. External content security settings are located in the Trust Center for Microsoft Excel only. You cannot change external content settings globally for Microsoft PowerPoint in the Trust Center. If you work in an organization, your system administrator might already have changed the default settings, and this might prevent you from changing any settings yourself.
Following are the different external content settings for Excel in the Trust Center. Click the option that you want under Security settings for Data Connections :.
Enable all Data Connections not recommended Click this option if you want to open workbooks that contain external data connections and to create connections to external data in the current workbook without receiving security warnings. We don't recommend this option, because connections to an external data source that you are not familiar with can be harmful, and because you do not receive any security warnings when you open any workbook from any location.
Use this option only when you trust the data sources of the external data connections. You may want to select this option temporarily, and then return to the default setting when you no longer need it. Prompt user about Data Connections This is the default option. Click this option if you want to receive a security warning whenever a workbook that contains external data connections is opened, and whenever an external data connection is created in the current workbook.
Security warnings give you the option of enabling or disabling data connections for each workbook that you open on a case-by-case basis. Disable all Data Connections Click this option if you don't want any external data connections to be enabled in the current workbook. When you choose this option, no data connection in any workbook that you open is ever connected.
If you create new external data connections after opening a workbook, those data connections are not enabled when you open the workbook again. This is a very restrictive setting, and may cause some functionality not to work as expected. Enable automatic update for all Workbook Links not recommended Click this option if you want links to data in another workbook to be updated automatically in the current workbook without receiving a security warning.
We don't recommend this option, because automatically updating links to data in workbooks that you are not familiar with can be harmful. Use this option only when you trust the workbooks that the data is linked to.
Prompt user on automatic update for Workbook Links This is the default option. Click this option if you want to receive a security warning whenever you run automatic updates in the current workbook for links to data in another workbook. Disable automatic update of Workbook Links Click this option if you don't want links in the current workbook to data in another workbook to be updated automatically.
When you create Linked data types , Excel connects to an online data source and returns detailed information about certain values, such as company stocks or geographies. For instance, converting the word Microsoft to a linked data type will return information about the Microsoft Corporation, such as location, number of employees, stock price, and so on.
Click the option that you want under Security settings for Linked Data Types :. Enable all Linked Data Types not recommended Click this option if you want to create linked data types without receiving a security warning. The data for linked data types is currently provided through Microsoft, but as with all external data, you should only choose this option if you trust the data source. Prompt user about Linked Data Types This is the default option. Click this option if you want to receive a security warning whenever you create linked data types.
Disable automatic update of Linked Data Types Click this option if you don't want to enable linked data types.. Dynamic Data Exchange DDE is an older Microsoft technology that transfers data between applications. Click the option that you want under Security settings for Dynamic Data Exchange :. Enable Dynamic Data Exchange Server Lookup Check this option if you want to enable Dynamic Data Exchange server lookup. If this option is checked, DDE servers that are already running will be visible and usable.
By default, this option is checked. Enable Dynamic Data Exchange Server Launch not recommended Check this option if you want to enable Dynamic Data Exchange server launch. For security reasons, it is recommended that you leave this box unchecked. By default, this option is unchecked. Using Microsoft Query , you can connect to external data sources, select data from those external sources, import that data into your worksheet, and refresh the data as needed to keep your worksheet data synchronized with the data in the external sources.
Always block the connection of untrusted Microsoft Query files. dqy, and. rqy Check this option if you want to block connections to Microsoft Query files. Images A hacker sends a workbook or presentation containing images for you to review. If there are images present in your workbook, when you open the file a business bar notifies you that the images have been disabled. Click Turn on images on the business bar if you want to unblock images. You should only do this if you are sure the images are coming from a trustworthy source.
You can always ask an expert in the Excel Tech Community or get support in the Answers community. Excel for Microsoft Word for Microsoft PowerPoint for Microsoft Excel for the web Excel Word PowerPoint Excel Word PowerPoint Excel Word PowerPoint Excel Word PowerPoint Excel Word PowerPoint Excel PowerPoint More Windows Web Mobile . What is external content, and why are Web beacons a potential threat?
Types of Web beacons include the following: Images A hacker sends a workbook or presentation for you to review that contains images. How does the Trust Center help protect me from external content?
What should I do when a security warning asks if I want to enable or disable external content? What is external content, and why are web beacons a potential threat? Types of Web beacons include the following: Images A hacker sends a workbook or presentation containing images for you to review.
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Click Options > Trust Center > Trust Center Settings, and then click External Content. Click the option that you want under Security settings for Linked Data Types: Enable all Linked Data 09/04/ · To restrict the formatting changes, follow the steps below. Select the Review Tab, then select Restrict Editing. Under Formatting Restrictions, select Settings. In the pop-up 10/07/ · Over the years, MS has blocked more file types by default. You can turn them on simply by clicking in the check boxes. First you have to decide what the check marks will do. 06/02/ · To enable this file type, do the following: Click the File tab. Under Help, click Options. Click Trust Center, and then click Trust Center Settings. In the Trust Center, ... read more
Click the option that you want under Security settings for Dynamic Data Exchange :. Email Required. You can follow the question or vote as helpful, but you cannot reply to this thread. Under Help, click Options. Dynamic Data Exchange DDE is an older Microsoft technology that transfers data between applications.
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