File Size Limits

OneDrive and SharePoint support individual file sizes up to 250GB currently.

Invalid Characters

Certain characters have special meanings when used in file names in OneDrive, SharePoint, Windows and macOS, such as "*" for wildcards, and "\" in file name paths. If a file or folder you’re trying to upload to OneDrive contains any of the characters listed below, it may prevent files and folders from syncing. Rename the file or folder to remove these characters before you upload it.

• " * : < > ? / \ | .
• Leading and trailing spaces in file or folder names also aren't allowed

Invalid File or Folder Names

These names aren't allowed for files or folders: .lock, CON, PRN, AUX, NUL, COM0 - COM9, LPT0 - LPT9, _vti_, desktop.ini, any filename starting with ~$. Also:

• "_vti_" cannot appear anywhere in a file name
• "forms" isn't supported when the folder is at the root level for a library.
• You can’t create a folder name in SharePoint that begins with a tilde (~).

Invalid or blocked file types

Temporary TMP files will not be synced to OneDrive. In addition, files that are used by your local computer, such as desktop.ini on Windows or .ds_store on macOS, don't normally sync. If these files do get uploaded to OneDrive during a migration, the sync app will delete the cloud copy and leave the local copy.

Outlook .PST files are are blocked from syncing by our organization as well. OneDrive cannot sync a PST while Outlook has it open, which can result in sync errors. We recommend moving Outlook PSTs to a folder location that is not synced by OneDrive.

File name and path length limits

Different apps and Office versions have different limits, and the combination of limitations may be unique to your setup.

The entire decoded file path, including the file name, can't contain more than 400 characters for OneDrive, and SharePoint in Microsoft 365. The limit applies to the combination of the folder path and file name after decoding.

In addition to the above, if files are synced to a PC or Mac, the following limitations apply:

• Each segment of the path (a segment is a file name or folder name like “Promotion” or “Some File.xlsx” in the examples above) can't be more than 255 characters due to operating system limitations.
• The length of the OneDrive root folder (e.g. C:\users\meganb\OneDrive - Contoso) + the relative path of the file (up to 400 chars) cannot be more than 520 characters.

For more details please see: https://support.microsoft.com/en-us/office/restrictions-and-limitations-in-onedrive-and-sharepoint-64883a5d-228e-48f5-b3d2-eb39e07630fa