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Author: Jonathan Stuckey

Considerations when reviewing contents of file-shares for migration.

SharePoint Online's ubiquity of file-support provides opportunity and challenges when migrating from file-share.

The list of file types actively blocked is quite small. The Microsoft guidance on Restrictions and limitations in OneDrive and SharePoint while useful, also misses out on highlighting considerations for a better outcome. The raft of information under Migrate your files to Microsoft 365 with Migration Manager | Microsoft Learn doesn't really provide a lot in the way of decision-making support, because it won't fit the specifics of your situation.

File-shares migrated using Microsoft SharePoint Migration Manager have challenges and scanning, reporting and planning for migration(s).

Microsoft 365 service only prevents a few file formats *but you really do not* want to take the following file-types if possible:

  1. Application executables and associated software file/library e.g. .exe, .dll,

  2. Files which store data for activity and chatty apps – i.e. live connections e.g. Access DB files (accdb) – these can cause issues with offline synchronisation management, and network scanning on file-walls.

  3. Windows desktop mgmt. files e.g. .thumbs, .ini files etc.

  4. Office and app temporary files and Outlook email files e.g. .tmp, .ost, .pst etc

  5. Web page, animation or scripting files are not blocked but wont run unless tenancy is configured to allow scripting therefore following types a constrained in working until updates applied

You will want to assess what you do with very-large sized file formats like large-scale multi-layered drawing formats, large media files etc – things upwards of 10GB per file. SharePoint and OneDrive will support individual files up to 250GB each, the ability to interact or update such a file will be constrained by your desktop management, device control, local network and your distance from a datacentre. If you are outside of major Microsoft datacentre hub, performance can be seriously impacted. (We don't all live in America...)

SharePoint can manage these file-types and these sizes, but app performance on your client device may not be what you want or need.

Planning migrations require data for good outcomes

File share migrations, contrary to popular myth, are not straight forward because they hide a multitude of solutions (and sins). File shares are often used to host:

Woman working office under precarious mountain of files and paper
File shares can be document chaos
  • User home-drive areas

  • Team and department shared files

  • Employee personnel files*

  • Desktop profile sync

  • Software installation points

  • Development code-store

  • Library and Archive content from 3rd parties

  • Database file stores - both desktop and enterprise database apps

  • Large-media storage for streaming or design tools

  • Large file storage for CAD or Drawing packages

  • Audio recordings from telephone and call-centre applications

  • Web CMS cache-files and back-ups

  • ....

Analysis of your shares and decent reporting is essential for helping the planning and decision process. Blocking identified files, like those singled-out in the previous section, can help smooth the way, but you will need to make decisions on what to do without them.

While Microsoft Migration Manager provides some scanning and analysis, its actually rubbish when you want to drill into your scan data to make decisions on what to take and what to leave. For a lot of small companies migrating though, it's all we have - because it's been paid-for when you bought Microsoft 365 licenses for Office, OneDrive etc.

Fall-back options are still the old-faithful ones like TreeSize, FolderSizes etc - but where these fall-down are that they don't allow you to transition from scan analysis data, to mapping to actual file-migration. Best tool in the market (my opinion) is still ShareGate migration tool. It costs - but its not expensive - and its very very effective and easy to use. It provides the scanning, standard reports with useful guidance and you can plumb it straight into your Microsoft SharePoint Online environment for point-to-point migration (and even batch the job). Best of both worlds.

Before signing off..

When you get reporting, take the opportunity to understand your content and try to clean and triage what you want to take - then get rid of the old stuff you don't need.

If you take everything over with no review you will not have another chance until you undergo a major organisation change or restructure. Don't 'kick the can down the road' - identify which stuff you don't want and clean-up first.

Want to know what we know? Give us a call!

If you want the best experience for your users, you need to know some of the tricks-of-the-trade and all the stuff Microsoft doesn't bother to tell you about what migrations really involve.

If you want to know about migrating from file-shares to SharePoint Online, drop us a line:

About the author: Jonathan Stuckey


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