Our add-in stopped working on Outlook for Windows New

Question

Our add-in (here) has suddenly stopped working on Outlook for Windows New: no task pane opens when we click the add-in icon.

This affects both versions installed from App Source and as sideload. We have also tried old versions of our code which we positively know worked on Outlook for Windows New.

We're testing on

Microsoft Outlook Version 1.2024.424.300 (Production).

Client Version is 20240419007.27 .

Here's our manifest:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<OfficeApp xmlns="http://schemas.microsoft.com/office/appforoffice/1.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:bt="http://schemas.microsoft.com/office/officeappbasictypes/1.0" xmlns:mailappor="http://schemas.microsoft.com/office/mailappversionoverrides/1.0" xsi:type="MailApp">
  <Id>55ec000a-faa4-4de9-a5a6-f39584a349d1</Id>
  <Version>1.0.0.0</Version>
  <ProviderName>Mixmax</ProviderName>
  <DefaultLocale>en-US</DefaultLocale>
  <DisplayName DefaultValue="Mixmax (local)"/>
  <Description DefaultValue="The Sales Engagement Platform built for B2B revenue teams."/>
  <IconUrl DefaultValue="https://outlook-add-in-local.mixmax.com/assets/logo-64.png"/>
  <HighResolutionIconUrl DefaultValue="https://outlook-add-in-local.mixmax.com/assets/logo-128.png"/>
  <SupportUrl DefaultValue="https://success.mixmax.com"/>
  <AppDomains>
    <AppDomain>https://mixmax.com</AppDomain>
    <!-- `displayDialogAsync` requires exact domains to be listed here -->
    <AppDomain>https://outlook-add-in-local.mixmax.com</AppDomain>
    <AppDomain>https://outlook-add-in-staging.mixmax.com</AppDomain>
    <AppDomain>https://outlook-add-in.mixmax.com</AppDomain>
    <AppDomain>https://app-local.mixmax.com</AppDomain>
    <AppDomain>https://app-staging.mixmax.com</AppDomain>
    <AppDomain>https://app-qa.mixmax.com</AppDomain>
    <AppDomain>https://app.mixmax.com</AppDomain>
  </AppDomains>
  <Hosts>
    <Host Name="Mailbox"/>
  </Hosts>
  <Requirements>
    <Sets>
      <Set Name="Mailbox" MinVersion="1.12"/>
    </Sets>
  </Requirements>
  <FormSettings>
    <Form xsi:type="ItemRead">
      <DesktopSettings>
        <SourceLocation DefaultValue="https://outlook-add-in-local.mixmax.com/taskpane.html"/>
        <RequestedHeight>250</RequestedHeight>
      </DesktopSettings>
    </Form>
  </FormSettings>
  <Permissions>ReadWriteMailbox</Permissions>
  <Rule xsi:type="RuleCollection" Mode="Or">
    <Rule xsi:type="ItemIs" ItemType="Message" FormType="Read"/>
  </Rule>
  <VersionOverrides xmlns="http://schemas.microsoft.com/office/mailappversionoverrides" xsi:type="VersionOverridesV1_0">
    <VersionOverrides xmlns="http://schemas.microsoft.com/office/mailappversionoverrides/1.1" xsi:type="VersionOverridesV1_1">
      <Requirements>
        <bt:Sets DefaultMinVersion="1.12">
          <bt:Set Name="Mailbox"/>
        </bt:Sets>
      </Requirements>
      <Hosts>
        <Host xsi:type="MailHost">
          <Runtimes>
            <!-- HTML file that references the JavaScript event handlers. This is used by Outlook on the web. -->
            <Runtime resid="Commands.Url">
              <!-- JavaScript file that contains the event handlers. This is used by Outlook on Windows. -->
              <Override type="javascript" resid="CommandsJS.Url"/>
            </Runtime>
          </Runtimes>
          <DesktopFormFactor>
            <FunctionFile resid="Commands.Url"/>
             <ExtensionPoint xsi:type="LaunchEvent">
              <LaunchEvents>
                <LaunchEvent Type="OnMessageCompose" FunctionName="onMessageComposeHandler"/>
                <LaunchEvent Type="OnMessageSend" FunctionName="onMessageSend"/>
              </LaunchEvents>
              <SourceLocation resid="Commands.Url" />
            </ExtensionPoint>
            <!-- Compose -->
            <ExtensionPoint xsi:type="MessageComposeCommandSurface">
              <OfficeTab id="TabDefault">
                <Group id="msgComposeGroup">
                  <Label resid="GroupLabel"/>
                  <Control xsi:type="Button" id="composeButton">
                    <Label resid="Compose.Label" />
                    <Supertip>
                      <Title resid="Compose.Label" />
                      <Description resid="ComposeButton.Tooltip" />
                    </Supertip>
                    <Icon>
                      <bt:Image size="16" resid="Icon.16x16"/>
                      <bt:Image size="32" resid="Icon.32x32"/>
                      <bt:Image size="80" resid="Icon.80x80"/>
                    </Icon>
                    <Action xsi:type="ShowTaskpane">
                      <SourceLocation resid="Compose.Url" />
                      <SupportsPinning>true</SupportsPinning>
                    </Action>
                  </Control>
                </Group>
              </OfficeTab>
            </ExtensionPoint>
          </DesktopFormFactor>
        </Host>
      </Hosts>
      <Resources>
        <bt:Images>
          <bt:Image id="Icon.16x16" DefaultValue="https://outlook-add-in-local.mixmax.com/assets/logo-16.png"/>
          <bt:Image id="Icon.32x32" DefaultValue="https://outlook-add-in-local.mixmax.com/assets/logo-32.png"/>
          <bt:Image id="Icon.80x80" DefaultValue="https://outlook-add-in-local.mixmax.com/assets/logo-80.png"/>
        </bt:Images>
        <bt:Urls>
          <bt:Url id="Commands.Url" DefaultValue="https://outlook-add-in-local.mixmax.com/commands.html"/>
          <bt:Url id="CommandsJS.Url" DefaultValue="https://outlook-add-in-local.mixmax.com/commands.js"/>
          <bt:Url id="Compose.Url" DefaultValue="https://outlook-add-in-local.mixmax.com/taskpane.html?route=/compose"/>
        </bt:Urls>
        <bt:ShortStrings>
          <bt:String id="GroupLabel" DefaultValue="Mixmax"/>
          <!-- Compose -->
          <bt:String id="Compose.Label" DefaultValue="Open Mixmax" />
        </bt:ShortStrings>
        <bt:LongStrings>
          <!-- Compose -->
          <bt:String id="ComposeButton.Tooltip" DefaultValue="Opens the Mixmax task pane for the compose mode."/>
        </bt:LongStrings>
      </Resources>
    </VersionOverrides>
  </VersionOverrides>
</OfficeApp>

There are no relevant errors in the dev console (when starting with olk.exe --devtools).

All hints will be welcome, including pointers to paid support services which will help us with this.

Answer 1

Hi @Jordi Salvat i Alabart ,

According to my search, this article provides solutions to common issues you might encounter after installing the Mixmax Add-in for Outlook: https://success.mixmax.com/en/articles/9042023-outlook-integration-troubleshooting-tips#h_dbf724cb2a(Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.)

It is recommended that you contact the support of this add-in for more professional help.

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