Create or edit web resources to extend an app

This topic applies to Dynamics 365 Customer Engagement (on-premises). For the Power Apps version of this topic, see: Create or edit model-driven app web resources to extend an app

Web resources are typically used by developers to extend an app using files that are used in web development. App users may need to manage web resources provided by a developer or designer.


For an in-depth discussion of web resources, see Web resources for Customer Engagement.

What are web resources?

Web resources are virtual files stored in the system. Each web resource has a unique name that can be used in a URL to retrieve the file. Think of them this way: If you had access to the actual web server running the web app, you could copy files over to that website. But with most online services, you can’t do this. Instead, you can use web resources to upload files to the system and then reference them by name just as though you had copied them as files to the web server.

For example, if you create an HTML page as a web resource named “new_myWebResource.htm”, you could open that page in a browser using a URL like this:

<Dynamics 365 Customer Engagement (on-premises) URL>/WebResources/new_myWebResource.htm

where <app URL> is the URL you usually use to open the app. Because the web resource is data in the system, only licensed users for your organization can access them this way. Normally, web resources are included in forms rather than referenced directly. The most common usage is to provide JavaScript libraries for form scripts.

Because web resources are data in the system and are solution aware, you can move them to different organizations by exporting them as part of a solution and importing the solution into a different organization.

Create and edit web resources

  1. Open solution explorer, and then select Web Resources.

  2. Under Components, choose Web Resources.

  3. To create a web resource select New.

    To edit a web resource double-click the web resource you want to edit.

  4. The web resource form has the following fields and capabilities:

    Label Description
    Name Required. This is the unique name for this web resource. You can’t change this after you save the web resource.

    This name can only include letters, numbers, periods, and nonconsecutive forward slash (“/”) characters.

    The solution publisher customization prefix will be prepended to the name of the web resource.
    Display Name The name displayed if you view a list of web resources.
    Description A description of the web resource.
    Type Required. This is the type of web resource. You can’t change this after you save the web resource.
    Text Editor When the type of web resource represents a kind of text file, select this button to open a page to edit the content using the text editor.
    Language Allows for a selection of a language. This option just tags the record that stores the web resource data. It doesn’t change the behavior of the web resource.
    Upload File Select the Browse… button to choose a file to upload as a web resource.

    You can upload a file when creating a new web resource or to overwrite an existing web resource.

    The file name extension of the file must match allowed extensions.

    By default the maximum size file that can be uploaded as a web resource is 5MB. This value can be modified in Dynamics 365 Customer Engagement (on-premises) by using the System Settings > Email tab > Set file size limit for attachments setting. More information: System Settings dialog box - Email tab
    URL After you save the web resource, the URL to the web resource will be displayed here. Select this link to view the web resource in your browser.
  5. After you have added your changes, choose Save and then Publish.


Publishing customizations can interfere with normal system operations. We recommend you publish customizations when it’s least disruptive to users.

Use the text editor appropriately

The text editor provided in the application for web resources should only be used for simple edits of text files. You can use it to create and edit HTML web resources, but you should only edit HTML web resources that were created using the text editor. The text editor is designed for very simple HTML content. If the content of an HTML web resource wasn’t created using the text editor, don’t use the text editor to edit it.

The text editor uses a control that modifies the HTML source in a way that allows it to be edited. These changes can make the page behave differently in the browser and cause more sophisticated code to stop working. Opening an HTML web resource with the text editor and saving it without making any changes can break some HTML web resources.

We recommend that you use an external editor to edit text files and then save them locally before uploading them with the Upload File button. This way you can preserve a copy of the web resource if you need to return to an earlier version. You can use a simple editor like Notepad, but a text editor with more advanced capabilities is highly recommended. Visual Studio Express is free and provides powerful capabilities for editing the files used by text-based web resources.

Create and edit a web resource on a form

You can add or edit web resources on a form to make it more appealing or useful to users. Make sure that you have the System Administrator security role or equivalent privileges.


You can’t include a web resource in a form header or footer.

  1. Open solution explorer.

  2. Under Components, expand Entities, and then expand the entity you want to work with.

  3. Choose Forms, in the list locate a form of type Main, and then double-click or tap the entry to open and edit the form.

  4. To add a web resource, select the tab (for example, General or Notes) you would like to insert it on, and then on the Insert tab, select Web Resource.
    To edit a Web resource, select a form tab and the web resource that you want to edit, and then on the Home tab, select Change Properties.

  5. In the Add Web Resource or Web Resource Properties dialog box, on the General tab, enter the appropriate information in the required fields. In particular, note the following:

    • In the Web resource box, select the image, HTML, or Silverlight web resource that you want to use.


      After you specify a web resource, the Web Resource Properties section appears at the bottom of this tab, providing options that vary based on the type of web resource you are adding. These options include specifying custom parameters, passing a record object-type code as a parameter, or specifying alternative text that describes the resource or, for images, that makes the image more accessible to all users. Here are a few important properties. For a complete listing, see: Web resource properties. - In the Name box, enter a unique name for the field. The name can contain only alphanumeric characters and underscores.

    • The Label field is automatically populated with a variation of the name you specify, but ensure that the proposed label meets your needs or update it accordingly.
  6. On the Formatting tab, the options that display vary based on the type of web resource inserted. These options include specifying the number of columns and rows display, whether a border displays, and the scrolling behavior.

  7. If the Dependencies tab displays in the Add Web Resource or Web Resource Properties dialog box, from the Available fields list, select the fields that are required by the Web resource, select the Add Selected Records button to move the selected fields to the Dependent fields list, and then select OK to close the dialog box.

  8. When you finish editing the form, on the Home tab, select Save and Close to close the form. To preview how the main form will appear and how events will function:

    • On the Home tab, select Preview, and then select Create Form, Update Form, or Read-Only Form.
    • To close the Preview form, on the File menu, select Close.
  9. When your customizations are complete, publish them:

    • To publish customizations for only the component that you are currently editing, in the navigation pane, select the entity you have been working on, and then select Publish.
    • To publish customizations for all unpublished components at one time, in the navigation pane, select Entities, and then on the Actions toolbar, select Publish All Customizations.

Add or edit an image web resource

Web resources are virtual files in multiple formats, such as html files, JavaScript, and Silverlight applications, that are stored in the system and can be retrieved by using a unique URL address.

  1. Open solution explorer.

  2. To create a new web resource, choose Components > Web Resources, and then on the Actions toolbar, choose New.

  3. Type or modify information in the text boxes.

    • The name entered in the Name text box, plus the file extension will become its file name.

    • The name entered in the Display Name text box will be displayed in the Display Name.

    • In the Type drop-down box, select the file type you want.

  4. Choose Browse to select and upload the file from your local machine.

    • To preview an uploaded image web resource: Choose Web Resource>Preview.

    • To edit a text web resource: Choose Text Editor.

    • To preview a text web resource: Choose Web Resource> Preview.

  5. When you’re ready to save your data, choose Save and Close.

  6. Publish your customization.

    • For only the edited component: Choose Save > Publish on the Home.

    • For all unpublished components at one time, choose Publish All Customizations.


Installing a solution or publishing customizations can interfere with normal system operation. We recommend that you schedule a solution import when it’s least disruptive to users.

See also

Web resource properties
Create and design forms
Get started with customization
Web resources for Customer Engagement