What Not to Move into Teams

Questions

  • Can we put our Microsoft Access database in a Teams channel?
  • Can I map a drive letter to a Teams channel?
  • Where should our QuickBooks company file go?
  • Can I store my Outlook archive or .pst file in Teams?
  • Our software needs a fixed file path. What do we do with its data?
  • Where does confidential or restricted data go if not into a Teams channel?
  • Why does our shared database create extra copies of itself when two people open it?
  • Can I keep virtual machine files or disk images in a Teams channel?
  • Should we move software installers and program folders into Teams?
  • As a department preparing to migrate, how do I flag a file that should not move?

Environment

This article applies to any Bowdoin department preparing to move shared files from the Microwave departmental drive (J:) into a Microsoft Team. Reviewing this list during the File Review, before the migration runs, means anything that does not belong gets flagged rather than copied.

  • Bowdoin-issued Windows 11 computers and Bowdoin-issued Macs running macOS Sequoia (15.x), Tahoe (26.x), or newer are supported. Personally owned computers are best-effort only.
  • Sign in to Microsoft 365 at https://office365.bowdoin.edu.
  • Your department's File Review spreadsheet is where each exception gets recorded. For how to fill it in, see Using the File Review Spreadsheet to Organize Your Department Files in the Related Articles section.
  • The individual file size limit in Microsoft Teams, SharePoint, and OneDrive is 250 GB, so size alone is rarely the reason something does not belong.
  • The problems described here appear whether a file is opened in a browser or through a synced folder on a computer.
  • Moving the files that do belong in a channel is a separate task. For that, see Transition Department Files to Microsoft Teams in the Related Articles section.

Resolution

Databases that more than one person opens

Microsoft Access and FileMaker company files hold a single file open and write to it constantly, and they rely on a lock file to keep two people from writing at the same moment. A synced Microsoft SharePoint library does not honor that lock. Microsoft states plainly that although you can save an Access database to OneDrive or a SharePoint library, "we recommend that you avoid opening an Access database from those locations," because "if more than one person opens the Access database from SharePoint, multiple copies of the database might be created and some unexpected behavior might occur."

Where it should go instead: a shared database belongs in a hosted database service, not on a file share. Microsoft's own recommendation for Access is to split the database and move the data to SQL Server or to SharePoint lists. Ask the Bowdoin College Service Desk about the right destination before moving a database anywhere.

Warning: Opening an Access or FileMaker file that two people share from a Teams channel can corrupt the file or quietly create competing copies. Deleted items in Microsoft Teams, SharePoint, and OneDrive are recoverable for 93 days, but a corrupted database file may not be recoverable at all.

Outlook data files with the .pst and .ost extensions

Microsoft Outlook does not support opening a .pst or .ost data file from any location that is not a local hard drive. Adding one from a network location or a mapped drive produces an "Invalid file name" or "Access denied" error. Microsoft also warns that using a .pst file over a network connection "may result in a corrupted .pst file if the connection degrades or fails."

Where it should go instead: mail belongs in the mailbox. Import the .pst file back into Outlook so the messages live in Microsoft Exchange, where they are backed up and searchable. If the file only needs to be kept as-is, copy it to a local drive.

Disk images and virtual machine files

Disk images and virtual machine files are large, change constantly while a virtual machine is running, and cannot be opened from a SharePoint library in a usable way. A running virtual machine writes to its disk file continuously, which produces a sync conflict every few minutes.

Where it should go instead: keep disk images and virtual machine files on local storage or an external drive. For archival copies, ask the Bowdoin College Service Desk about a location for bulk archive storage.

Application installers and program folders

Installers take up library space and go out of date. A program folder run from a SharePoint library breaks, because programs expect every one of their files to be present and unchanged, and Files On-Demand may not have downloaded them yet.

Where it should go instead: leave installers and program folders where they are. Bowdoin-managed Macs offer approved software through Jamf Pro Self Service, Bowdoin-managed Windows 11 computers offer it through Intune Company Portal, and anything not listed there can be requested from the Bowdoin College Service Desk.

Anything that needs a fixed drive letter or UNC path

Mapping a drive letter to a Microsoft Teams channel is not possible. Mapping relies on WebDAV, which Microsoft describes as "an older technology which is slower and less reliable than syncing SharePoint files with the new OneDrive sync client," and it is not the way to reach a Teams library. No supported way exists to give a Teams channel a J:-style drive letter or a Universal Naming Convention (UNC) path such as \\server\share.

Where it should go instead: when a piece of software requires a fixed path, that software's data cannot move to Microsoft Teams. Record the software and its data in your department's File Review spreadsheet and raise it with the Bowdoin College Service Desk so a destination can be arranged before the old Microwave (J:) drive is removed.

Large scratch and working sets

Rendering output, scientific intermediates, and other files that are written, read once, and deleted create constant sync traffic and fill version history with copies nobody wants. Large scratch sets also count against Microsoft's recommendation to sync no more than 300,000 items in total.

Where it should go instead: keep the working set on local storage or research storage and move only the finished output into the Teams channel.

Software license and activation files

License and activation files are usually tied to one specific machine, so a copy in a shared channel is both useless and a licensing risk.

Where it should go instead: leave license files where the software installed them, and keep the purchase records in the Teams channel instead.

Restricted data

Records that identify individuals, financial account details, health information, and anything else classified as restricted should not be copied into a general department channel. A Team's files are visible to every member of the Team.

Where it should go instead: an approved system for that record type, or a channel with restricted membership and the correct sensitivity label applied. For labels, see Add or Change Sensitivity Labels for Files and Teams in Microsoft 365 in the Related Articles section, and confirm the destination with the Bowdoin College Service Desk before moving restricted records.

When you are not sure, ask before you move it

Answering a question before a migration is far easier than recovering data afterward. Note the file in your department's File Review spreadsheet, leave the file on the old Microwave (J:) drive, and ask the Bowdoin College Service Desk.

Important: Flag every exception in your department's File Review spreadsheet before the migration runs. A file copied into a channel and only then found not to belong has to be removed by hand, and any edits made to the channel copy have to be reconciled by hand as well.

Additional Help

If you need further assistance, you have several options:

  • Bowdoin Bot: Chat with Bowdoin Bot directly from any KB page for instant answers.
  • Phone: Call the Bowdoin College Service Desk at (207) 725-3030.
  • In person: Visit the Tech Hub in Smith Union during business hours.
  • Submit a ticket: Request assistance through the Service Catalog.

Additional Resources

 

 

AI-assisted content: This article was created with AI. It was verified and edited by a human.
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