Advisory message regarding Cloud Drive Mapper V2 and Office update 2411 and 2412

This incident has been resolved.

Version 2501 (Build 18429.20088) is now in the current channel, this has been tested and so far it is not affected by the issue. We're continuing to monitor the situation and are still engaging with Microsoft on this.

If that version of Office isn't available to you, a work around is to add your tenant address to the registry as instructed in this guide - https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/credentials-prompt-access-webdav-fqdn-sites

This allows PowerPoint files to open normally from the mapped drives.

Update as of 20/01:

2411 and 2412 are now in the current channel. The issues is still present on these versions. We have also tested 2501 and 2502, these still have the issue too. We're still engaging with Microsoft in order to ascertain further information on this issue.

The current options are:

Use PowerPoint online;
Open PowerPoint locally then, Open > Browse > This PC;
Use the pre release version of CDM V3. If you are not already in this program let us know and we can get you set up. Details are on - https://www.iamcloud.com/iam-blog/news-cdm-v3-pre-release-update/ and cdm.iamcloud.info.

If you have a Microsoft sales or support representative please let them know about this issue linking our status above as an explanation. We would be happy to engage with them and link them to our own open ticket to bring this to a successful resolution.

If you have any further questions then please contact support@iamcloud.com.

We have become aware of an upcoming issue whereby users with WebDAV-based mapped OneDrive and SharePoint drives are unable to open .pptx files. This is currently manifesting in Preview Channel MS Office versions progressing through the Microsoft Beta program.

This issue is introduced in MS Office version 2411. If you currently use WebDAV-based mapped drives to access networked .pptx files, and are due to receive this Office version as part of Microsoft's standard release process, then our testing indicates that the file access will fail.

We have tested our v2.x CDM client (which uses WebDAV) with the upcoming Office version and have found that our service is also impacted; i.e. CDM-initiated .pptx file operations will also fail for users who receive and install Office version 2411.

Note that impact to CDM users is conditional on;

- The upcoming Office version 2411
- File operations that take place on .pptx file types (earlier PowerPoint files are not affected)

Users who do not move to the impacted Office version or do not interact with .pptx files in this way should not be affected. Should our understanding of this impact change through further testing we will inform you via this Status Page.

We have reached out to Microsoft through various channels to inform them of this breaking change. At present we do not have an accurate time scale as to when Office users (and therefore downstream CDM users) may be impacted as this is dependent on Microsoft's rollout schedules and your own upgrade processes.

You may wish to postpone upgrading to MS Office 2411 if possible to avoid potential impacts, and to provide more time for Microsoft to issue a fix or to plan service migration to CDM v3.

For customers who are concerned that they fall within the impacted population we can provide mitigation through migration to our Pre-release v3 client, which is not impacted by the MS Office v2411 change. Customers who wish to migrate will be able to fully test the v3 client to ensure our Pre-release version meets operational requirements. Should you wish to discuss this option then please contact us via support@iamcloud.com.

For those customers who may not wish to migrate to v3 yet or have functional requirements which are not yet met by v3 there are two main options available;

1) Access .pptx files via a web browser
2) Report issues to Microsoft Support if you become impacted by the Office 2411 version release

It is important to note that this issue relates to the relationship between Microsoft’s WebDAV and PowerPoint components and is not specific to CDM v2. CDM v2 is impacted due to its usage of the WebDAV protocol which v3 does not rely on and is therefore not affected.

Our summary of the issue is below; this may assist describing the issue to Microsoft should you require;

If you open a drive mapped via Microsoft Edge’s "View in File Explorer” function when browsing SharePoint Online (this is the manual way of creating a WebDAV-based drive in Windows), from that drive you cannot open PowerPoint files if you have upgraded to Office 2411.

When opening a .pptx you will be given a message stating 'Sorry, PowerPoint can't read 'path and file name'.pptx'