[All Hosts] (manifest) EquivalentAddin applies to VSTO too (#2309)

Rick-Kirkham · samantharamon · web-flow · commit 82ecff4c5e25 · 2025-07-10T13:45:36.000-07:00
* [All Hosts] (manifest) EquivalentAddin applies to VSTO too

* Apply suggestions from code review

Co-authored-by: Sam Ramon &lt;15154970+samantharamon@users.noreply.github.com&gt;

---------

Co-authored-by: Sam Ramon &lt;15154970+samantharamon@users.noreply.github.com&gt;
diff --git a/docs/includes/equivalent-add-in-support-note.md b/docs/includes/equivalent-add-in-support-note.md
@@ -1,5 +1,5 @@
 > [!IMPORTANT]
-> The equivalent add-in feature is supported by the following platform and applications. COM add-ins cannot be installed on any other platform, so on those platforms the manifest element that is discussed later in this article, `EquivalentAddins`, is ignored.
+> The equivalent add-in feature is supported by the following platform and applications. COM and VSTO add-ins can't be installed on any other platform, so on those platforms the manifest element that's discussed later in this article is ignored.
 >
 > - Excel, Word, and PowerPoint on Windows (Version 1904 or later)
 > - Outlook on Windows (Version 2102 or later) against a supported Exchange server version
diff --git a/docs/manifest/equivalentaddin.md b/docs/manifest/equivalentaddin.md
@@ -1,13 +1,13 @@
 ---
 title: EquivalentAddin element in the manifest file
-description: Specifies backwards compatibility for an equivalent COM add-in or XLL.
-ms.date: 01/04/2022
+description: Specifies backwards compatibility for an equivalent COM or VSTO add-in or XLL.
+ms.date: 07/12/2025
 ms.localizationpriority: medium
 ---
 
 # EquivalentAddin element
 
-Specifies backwards compatibility for an equivalent COM add-in or XLL.
+Specifies backwards compatibility for an equivalent COM add-in, VSTO add-in, or XLL.
 
 [!INCLUDE [Support note for equivalent add-ins feature](../includes/equivalent-add-in-support-note.md)]
 
@@ -43,9 +43,16 @@ For more information, see [Version overrides in the add-in only manifest](/offic
 
 ## Remarks
 
-To specify a COM add-in as the equivalent add-in, provide both the `ProgId` and `Type` elements. To specify an XLL as the equivalent add-in, provide both the `FileName` and `Type` elements.
+To specify a COM or VSTO add-in as the equivalent add-in, provide both the `ProgId` and `Type` elements. 
+
+> [!NOTE]
+>
+> - Although the term "ProgId" is usually associated with only COM add-ins, in the manifest it refers to the name of either a COM or VSTO add-in.
+> - Use `COM` as the value of the `Type` element for both COM and VSTO add-ins.
+
+To specify an XLL as the equivalent add-in, provide both the `FileName` and `Type` elements.
 
 ## See also
 
 - [Make your custom functions compatible with XLL user-defined functions](/office/dev/add-ins/excel/make-custom-functions-compatible-with-xll-udf)
-- [Make your Office Add-in compatible with an existing COM add-in](/office/dev/add-ins/develop/make-office-add-in-compatible-with-existing-com-add-in)
+- [Make your Office Add-in compatible with an existing COM or VSTO add-in](/office/dev/add-ins/develop/make-office-add-in-compatible-with-existing-com-add-in)
diff --git a/docs/manifest/equivalentaddins.md b/docs/manifest/equivalentaddins.md
@@ -1,13 +1,13 @@
 ---
 title: EquivalentAddins element in the manifest file
-description: Specifies backwards compatibility with an equivalent COM add-in, XLL, or both.
-ms.date: 01/04/2022
+description: Specifies backwards compatibility with one or more equivalent COM or VSTO add-ins or XLLs.
+ms.date: 07/12/2025
 ms.localizationpriority: medium
 ---
 
 # EquivalentAddins element
 
-Specifies backwards compatibility with an equivalent COM add-in, XLL, or both.
+Specifies compatibility with one or more equivalent COM add-ins, VSTO add-ins, or XLLs.
 
 [!INCLUDE [Support note for equivalent add-ins feature](../includes/equivalent-add-in-support-note.md)]
 
@@ -39,4 +39,4 @@ For more information, see [Version overrides in the add-in only manifest](/offic
 ## See also
 
 - [Make your custom functions compatible with XLL user-defined functions](/office/dev/add-ins/excel/make-custom-functions-compatible-with-xll-udf)
-- [Make your Office Add-in compatible with an existing COM add-in](/office/dev/add-ins/develop/make-office-add-in-compatible-with-existing-com-add-in)
+- [Make your Office Add-in compatible with an existing COM or VSTO add-in](/office/dev/add-ins/develop/make-office-add-in-compatible-with-existing-com-add-in)
diff --git a/docs/manifest/progid.md b/docs/manifest/progid.md
@@ -1,13 +1,13 @@
 ---
 title: ProgId element in the manifest file
-description: The ProgId element specifies the programmatic ID of the equivalent COM add-in for your web add-in's task pane.
-ms.date: 03/09/2021
+description: The ProgId element specifies the programmatic ID of the equivalent COM or VSTO add-in for your web add-in's task pane.
+ms.date: 07/12/2025
 ms.localizationpriority: medium
 ---
 
 # ProgId element
 
-Specifies the programmatic identifier of the equivalent COM add-in for the task pane of your web add-in.
+Specifies the name of the equivalent COM or VSTO add-in for your web add-in.
 
 **Add-in type:** Task pane
 
@@ -24,4 +24,4 @@ Specifies the programmatic identifier of the equivalent COM add-in for the task
 ## See also
 
 - [Make your custom functions compatible with XLL user-defined functions](/office/dev/add-ins/excel/make-custom-functions-compatible-with-xll-udf)
-- [Make your Office Add-in compatible with an existing COM add-in](/office/dev/add-ins/develop/make-office-add-in-compatible-with-existing-com-add-in)
+- [Make your Office Add-in compatible with an existing COM or VSTO add-in](/office/dev/add-ins/develop/make-office-add-in-compatible-with-existing-com-add-in)
diff --git a/docs/manifest/type.md b/docs/manifest/type.md
@@ -1,13 +1,13 @@
 ---
 title: Type element in the manifest file
-description: The Type element specifies if the equivalent add-in is a COM add-in or an XLL.
-ms.date: 03/09/2021
+description: The Type element specifies if the equivalent add-in is a COM or VSTO add-in or an XLL.
+ms.date: 07/12/2025
 ms.localizationpriority: medium
 ---
 
 # Type element
 
-Specifies if the equivalent add-in is a COM add-in or an XLL.
+Specifies if the equivalent add-in is a COM or VSTO add-in or an XLL.
 
 **Add-in type:** Task pane, Custom function
 
@@ -25,10 +25,13 @@ Specifies if the equivalent add-in is a COM add-in or an XLL.
 
 You must specify one of the following values for the `Type` element.
 
-- COM: Specifies the equivalent add-in is a COM add-in.
+- COM: Specifies the equivalent add-in is a COM or a VSTO add-in.
 - XLL: Specifies the equivalent add-in is an Excel XLL.
 
+> [!IMPORTANT]
+> Use `COM` as the value of the `Type` element for both COM and VSTO add-ins.
+
 ## See also
 
 - [Make your custom functions compatible with XLL user-defined functions](/office/dev/add-ins/excel/make-custom-functions-compatible-with-xll-udf)
-- [Make your Office Add-in compatible with an existing COM add-in](/office/dev/add-ins/develop/make-office-add-in-compatible-with-existing-com-add-in)
+- [Make your Office Add-in compatible with an existing COM or VSTO add-in](/office/dev/add-ins/develop/make-office-add-in-compatible-with-existing-com-add-in)

Original file line number	Diff line number	Diff line change
`@@ -1,5 +1,5 @@`
`1`	`1`	`> [!IMPORTANT]`
`2`		-> The equivalent add-in feature is supported by the following platform and applications. COM add-ins cannot be installed on any other platform, so on those platforms the manifest element that is discussed later in this article, `EquivalentAddins`, is ignored.
	`2`	`+> The equivalent add-in feature is supported by the following platform and applications. COM and VSTO add-ins can't be installed on any other platform, so on those platforms the manifest element that's discussed later in this article is ignored.`
`3`	`3`	`>`
`4`	`4`	`> - Excel, Word, and PowerPoint on Windows (Version 1904 or later)`
`5`	`5`	`> - Outlook on Windows (Version 2102 or later) against a supported Exchange server version`