If you are experiencing issues with your Outlook add-in, depending on whether you are using the web version or the desktop version of Outlook, there could be a few different reasons.
To minimize potential user disruption due to delays in IT authorization, we will release the New App as a separate Add-In rather than updating the existing one. This allows it to be installed alongside the legacy app, enabling a smoother transition for early adopters.
NOTE: The Legacy Outlook Add-In will have an end-of-life approximately 6 months after the release of the new Add-In
All users can use the new add-in upon release, except where permission changes require approval. In those cases, email/document filing will be unavailable until consent is granted by an admin or the user, based on their organization's settings.
Frequently Asked Questions
Can teams continue using existing add-in - how long for?
Can teams continue using existing add-in - how long for?
The legacy app will be available (albeit with limited support) for approximately 6 months after the release of the new add-in (~Feb 2026)
Customers are encouraged to begin the transition process to adopting the new Add-In.
Depending on how the legacy Add-In was installed customers will experience the following:
Users installed the add-in from the MS app store and have no restrictions on which apps they can install
These users will get the update automatically and very shortly after it is published
User can install the add-in from the MS app store. They can also uninstall the legacy app.
Users installed the add-in from the MS app store and have restrictions
I would expect most of these users to get the update, however there may be restrictions or approvals required due to permission changes
After the permissions and authorisations have been completed by the customers IT team they can install the add-in from the MS app store. They can also uninstall the legacy app.
Admin deployed the add-in from the app store to users
I would expect most of these users to get the update, however there may be restrictions or approvals required due to permission changes.
After the permissions and authorisations have been completed by the customers IT team and deployed, users can install the add-in from the MS app store. They can also uninstall the legacy app.
Admin deployed the add-in via a manifest to users
A manual redeployment via a manifest file is needed
Individual user manually installed the manifest
A manual install of the update is required
We note that as with the initially implementation we need to ‘Grant Admin Consent’ for the new enterprise app, will we revoke this access once the new application has been configured, as we did after the initial Outlook Plug-in implementation?
We note that as with the initially implementation we need to ‘Grant Admin Consent’ for the new enterprise app, will we revoke this access once the new application has been configured, as we did after the initial Outlook Plug-in implementation?
The admin consent should not be revoked.
We also note that the write permission is required to add filing metadata such as categories to emails. Can we have more details regarding this?
We also note that the write permission is required to add filing metadata such as categories to emails. Can we have more details regarding this?
The write permissions is used to add the 'Filed by Xakia' category to indicate that emails have been filed. This is part of the 'Xakia Filing Indicator' feature. The add-in only ever accesses email for users that use the Xakia O365 Outlook add-in, and only ever accesses email items that are requested by the user.
With regards to the Outlook metadata that is being added how would this be cleaned up if we were to terminate our agreement with Xakia or is this technical debt left for us to clean up?
With regards to the Outlook metadata that is being added how would this be cleaned up if we were to terminate our agreement with Xakia or is this technical debt left for us to clean up?
Assuming the metadata you note is related to the point above, Xakia is unable to determine when the add-in is removed from a users mailbox and so is unable to remove categories at this time. ***Internal note: This may be possible as a paid back-end script, but we are not advising this upfront.
How does the Conversation / Thread filing work in Outlook / Xakia Outlook Add-In?
How does the Conversation / Thread filing work in Outlook / Xakia Outlook Add-In?
Xakia's Outlook Add-In leverages the native Outlook Conversation functionality to determine if a email belongs to a Conversation thread.
Outlook groups emails into conversations (threads) based on several key factors to automatically file related messages together.
How Outlook Classifies a Conversation
Subject Line
Outlook looks at the email’s subject line. Emails with the exact same subject (ignoring common prefixes like “Re:” or “Fwd:”) are candidates for the same conversation.
Minor differences or changes in the subject can cause Outlook to treat emails as separate threads.
Message Headers
Outlook uses email headers such as Conversation Index and Conversation Topic.
The Conversation Topic is derived from the original subject but can remain consistent even if the subject changes slightly.
The Conversation Index helps Outlook understand the sequence and hierarchy of replies.
Participants
While less critical than subject and headers, Outlook also considers the sender and recipients.
If emails with the same subject are between the same or overlapping sets of people, they’re more likely to be grouped.
Threading Logic
Outlook relies on the Internet Message-ID and References headers to link replies to the original message.
These headers create a chain of emails that Outlook uses to maintain the conversation structure.