[office-js][office-js-preview] (Outlook) Update length of an attachment's Base64-encoded string (DefinitelyTyped#74867)

samantharamon · web-flow · commit a2a1b7a379e5 · 2026-04-10T15:06:47.000-07:00
diff --git a/types/office-js-preview/index.d.ts b/types/office-js-preview/index.d.ts
@@ -11307,7 +11307,7 @@ declare namespace Office {
          *
          * - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
          *
-         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).
+         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.
          * @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.
          * @param options - An object literal that contains one or more of the following properties:-
          *        `asyncContext`: Developers can provide any object they wish to access in the callback function.
@@ -11354,7 +11354,7 @@ declare namespace Office {
          *
          * - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
          *
-         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).
+         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.
          * @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.
          * @param callback - Optional. When the method completes, the function passed in the `callback` parameter is called with a single parameter
          *                             of type `Office.AsyncResult`.
@@ -20207,7 +20207,7 @@ declare namespace Office {
          *
          * - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
          *
-         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).
+         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.
          * @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.
          * @param options - An object literal that contains one or more of the following properties:-
          *        `asyncContext`: Developers can provide any object they wish to access in the callback function.
@@ -20263,7 +20263,7 @@ declare namespace Office {
          *
          * - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
          *
-         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).
+         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.
          * @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.
          * @param callback - Optional. When the method completes, the function passed in the `callback` parameter is called with a single parameter of type `Office.AsyncResult`.
          *                 On success, the attachment identifier is provided in the `asyncResult.value` property. The identifier varies depending on the Outlook client.
diff --git a/types/office-js/index.d.ts b/types/office-js/index.d.ts
@@ -11265,7 +11265,7 @@ declare namespace Office {
          *
          * - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
          *
-         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).
+         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.
          * @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.
          * @param options - An object literal that contains one or more of the following properties:-
          *        `asyncContext`: Developers can provide any object they wish to access in the callback function.
@@ -11312,7 +11312,7 @@ declare namespace Office {
          *
          * - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
          *
-         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).
+         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.
          * @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.
          * @param callback - Optional. When the method completes, the function passed in the `callback` parameter is called with a single parameter
          *                             of type `Office.AsyncResult`.
@@ -19677,7 +19677,7 @@ declare namespace Office {
          *
          * - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
          *
-         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).
+         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.
          * @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.
          * @param options - An object literal that contains one or more of the following properties:-
          *        `asyncContext`: Developers can provide any object they wish to access in the callback function.
@@ -19733,7 +19733,7 @@ declare namespace Office {
          *
          * - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
          *
-         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).
+         * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.
          * @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.
          * @param callback - Optional. When the method completes, the function passed in the `callback` parameter is called with a single parameter of type `Office.AsyncResult`.
          *                 On success, the attachment identifier is provided in the `asyncResult.value` property. The identifier varies depending on the Outlook client.

Original file line number	Diff line number	Diff line change
`@@ -11307,7 +11307,7 @@ declare namespace Office {`
`11307`	`11307`	`*`
`11308`	`11308`	* - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
`11309`	`11309`	`*`
`11310`		`- * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).`
	`11310`	`+ * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.`
`11311`	`11311`	`* @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.`
`11312`	`11312`	`* @param options - An object literal that contains one or more of the following properties:-`
`11313`	`11313`	* `asyncContext`: Developers can provide any object they wish to access in the callback function.
`@@ -11354,7 +11354,7 @@ declare namespace Office {`
`11354`	`11354`	`*`
`11355`	`11355`	* - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
`11356`	`11356`	`*`
`11357`		`- * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).`
	`11357`	`+ * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.`
`11358`	`11358`	`* @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.`
`11359`	`11359`	* @param callback - Optional. When the method completes, the function passed in the `callback` parameter is called with a single parameter
`11360`	`11360`	* of type `Office.AsyncResult`.
`@@ -20207,7 +20207,7 @@ declare namespace Office {`
`20207`	`20207`	`*`
`20208`	`20208`	* - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
`20209`	`20209`	`*`
`20210`		`- * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).`
	`20210`	`+ * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.`
`20211`	`20211`	`* @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.`
`20212`	`20212`	`* @param options - An object literal that contains one or more of the following properties:-`
`20213`	`20213`	* `asyncContext`: Developers can provide any object they wish to access in the callback function.
`@@ -20263,7 +20263,7 @@ declare namespace Office {`
`20263`	`20263`	`*`
`20264`	`20264`	* - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
`20265`	`20265`	`*`
`20266`		`- * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).`
	`20266`	`+ * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.`
`20267`	`20267`	`* @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.`
`20268`	`20268`	* @param callback - Optional. When the method completes, the function passed in the `callback` parameter is called with a single parameter of type `Office.AsyncResult`.
`20269`	`20269`	* On success, the attachment identifier is provided in the `asyncResult.value` property. The identifier varies depending on the Outlook client.
Original file line number	Diff line number	Diff line change
`@@ -11265,7 +11265,7 @@ declare namespace Office {`
`11265`	`11265`	`*`
`11266`	`11266`	* - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
`11267`	`11267`	`*`
`11268`		`- * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).`
	`11268`	`+ * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.`
`11269`	`11269`	`* @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.`
`11270`	`11270`	`* @param options - An object literal that contains one or more of the following properties:-`
`11271`	`11271`	* `asyncContext`: Developers can provide any object they wish to access in the callback function.
`@@ -11312,7 +11312,7 @@ declare namespace Office {`
`11312`	`11312`	`*`
`11313`	`11313`	* - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
`11314`	`11314`	`*`
`11315`		`- * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).`
	`11315`	`+ * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.`
`11316`	`11316`	`* @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.`
`11317`	`11317`	* @param callback - Optional. When the method completes, the function passed in the `callback` parameter is called with a single parameter
`11318`	`11318`	* of type `Office.AsyncResult`.
`@@ -19677,7 +19677,7 @@ declare namespace Office {`
`19677`	`19677`	`*`
`19678`	`19678`	* - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
`19679`	`19679`	`*`
`19680`		`- * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).`
	`19680`	`+ * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.`
`19681`	`19681`	`* @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.`
`19682`	`19682`	`* @param options - An object literal that contains one or more of the following properties:-`
`19683`	`19683`	* `asyncContext`: Developers can provide any object they wish to access in the callback function.
`@@ -19733,7 +19733,7 @@ declare namespace Office {`
`19733`	`19733`	`*`
`19734`	`19734`	* - `NumberOfAttachmentsExceeded`: The message or appointment has too many attachments.
`19735`	`19735`	`*`
`19736`		`- * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 27,892,122 characters (about 25 MB).`
	`19736`	`+ * @param base64File - The Base64-encoded content of an image or file to be added to an email or event. The maximum length of the encoded string is 34,865,152 characters. This corresponds to a maximum attachment size of 25 MB before Base64 encoding.`
`19737`	`19737`	`* @param attachmentName - The name of the attachment that is shown while the attachment is uploading. The maximum length is 255 characters.`
`19738`	`19738`	* @param callback - Optional. When the method completes, the function passed in the `callback` parameter is called with a single parameter of type `Office.AsyncResult`.
`19739`	`19739`	* On success, the attachment identifier is provided in the `asyncResult.value` property. The identifier varies depending on the Outlook client.