SharePoint can be finicky about what you put it in and what you call, well, what you put in it. Certain file types are a no-no, and a number of special characters and some permutations of periods aren’t allowed.


The reason behind each of these limitations varies. Some are kind of obvious (percent signs, for example, are used in the URL of a file that uses acceptable special characters) and others make no sense (I still don’t get why SharePoint, a database itself, can’t accept an Access 2003 file, which is a database file).


Don’t worry about the why. It took me a long time to get over that because I always want to know the “why” about everything. There are just so many different ones for the various file types and naming options that it’s not worth pulling your hair out over.


Special characters you can’t use

Here are the limitations that come with what you can name a file in SharePoint 2013 (SP2013), SP2016, and SharePoint Online (SPO). The symbol comes first, then a dash, then the title of the symbol. (Point being, don’t mistake the dash for part of the symbol!)


  • SharePoint 2013, SharePoint 2016, SharePoint Online, OneDrive for Business (source):
    • ” – quotation mark
    • # – pound, hashtag, number sign
    • % – percent sign
    • * – asterisk, star
    • : – colon (I’m surprised the semicolon is allowed)
    • < – less than symbol
    • > – greater than symbol
    • ? – question mark
    • / – forward slash
    • \ – backslash
    • | – vertical bar, also known as the “pipe” symbol
  • Additionally, if your system uses OneDrive for Business on SP2013 (rare, but does exist), a couple more characters are added to the list (source):
    • ~ – tilde
    • & – ampersand, “and” symbol
    • { – opening brace (also known as “curly bracket”)
    • } – closing brace (also known as “curly bracket”)


File and folder name length

Because of limitations with how long a web address or URL can be in some browsers (cough**Internet Explorer**cough), there is a limit to the number of characters you can have in the name of a file being uploaded to SharePoint. Doesn’t matter whether it’s going into a document library or being attached to a list item. This applies similarly to folders, which are restricted to document libraries.


File and folder names have the following character limits:

  1. File names are limited to 128 characters in SP2013 and 256 characters in SPO.
  2. Folder names are limited to 256 characters.
  3. Most importantly, the combination of folder path plus file name is limited to 260 characters. These are all boundaries (i.e., hard limits). Be careful of nested folders! This can really bite you in the rear!
    (Note: the source for this limit is based on a SP 2010 article, but from research, it appears no changes occurred in the SP2013/SPO release.)

Okay, so why does this last item matter? Because people love folders. For some reason, a seemingly endless tree of folders appears to really bring warmth to the hearts of far too many people. And that can lead to a really bad day for you if you do. Why?

Think about this example: a folder tree that has the following structure…

  • Finance Department Annual Budget for 2016
    • Supporting Documentation for 2016 Budget
      • Initial 2016 Budget Draft for Executive Committee Review
        • Budget 2016 Draft Documents Signed Off for Sharing Internally
          • Marys Initial Comments on Budget
            • InitialDocumentReviewForSignOffFollowingCFOReview-Mary.docx

This won’t open correctly in your browser once you browse to the deepest levels. It totals 261 characters, which breaks the 260-character limit.

If you think that folder structure seems insane, good. Now look around at your colleagues. Most of them won’t. Trust me. This happens all the time.


Unsupported file types

Back when I started using SharePoint, SP2007 was the version du jour. And it was awful in the number of file types it didn’t support. Some were flat out astounding. Since then, Microsoft has made up for past mistakes and SharePoint 2013 now accepts pretty much anything that’s not an executable file or script (aka a computer program), some HTML and JavaScript files (believe it or not), and a surprisingly large assortment of shortcut files.


And best of all, SharePoint Online does not block any file types. (Your IT department can always impose a block if they want, though.)


The file types that aren’t supported by SP2010 and SP2013, are as follows (source):

.ade Microsoft Access project extension
.adp Microsoft Access project
.asa ASP declarations file
.ashx ASP.NET Web handler file. Web handlers are software modules that handle raw HTTP requests received by ASP.NET.
.asmx ASP.NET Web Services source file
.asp Active Server Pages
.bas Microsoft Visual Basic class module
.bat Batch file
.cdx Compound index
.cer Certificate file
.chm Compiled HTML Help file
.class Java class file
.cmd Microsoft Windows NT command script
.com Microsoft MS-DOS program
.config Configuration file
.cnt Help Contents file
.cpl Control Panel extension
.crt Security certificate
.csh Script file
.der DER Certificate file
.dll Windows dynamic-link library
.exe Executable file
.fxp Microsoft Visual FoxPro compiled program
.gadget Windows Gadget
.grp SmarterMail group file
.hlp Help file
.hpj Hemera Photo Objects Image File
.hta HTML program
.htr Script file
.htw HTML document
.ida Internet Information Services file
.idc Internet database connector file
.idq Internet data query file
.ins Internet Naming Service
.isp Internet Communication settings
.its Internet Document Set file
.jse JScript Encoded script file
.json JavaScript Object Notation file
.ksh Korn Shell script file
.lnk Shortcut
.mad Shortcut
.maf Shortcut
.mag Shortcut
.mam Shortcut
.maq Shortcut
.mar Shortcut
.mas Microsoft Access stored procedure
.mat Shortcut
.mau Shortcut
.mav Shortcut
.maw Shortcut
.mcf Multimedia Container Format
.mda Microsoft Access add-in program
.mdb Microsoft Access program
.mde Microsoft Access MDE database
.mdt Microsoft Access data file
.mdw Microsoft Access workgroup
.mdz Microsoft Access wizard program
.ms-one-stub Microsoft OneNote stub
.msc Microsoft Common Console document
.msh Microsoft Agent script helper
.msh1 Microsoft Agent script helper
.msh1xml Microsoft Agent script helper
.msh2 Microsoft Agent script helper
.msh2xml Microsoft Agent script helper
.mshxml Microsoft Agent script helper
.msi Microsoft Windows Installer package
.msp Windows Installer update package file
.mst Visual Test source files
.ops Microsoft Office profile settings file
.pcd Photo CD image or Microsoft Visual Test compiled script
.pif Shortcut to MS-DOS program
.pl Perl script
.prf System file
.prg Program source file
.printer Printer file
.ps1 Windows PowerShell Cmdlet file
.ps1xml Windows PowerShell Display configuration file
.ps2 Windows PowerShell Cmdlet file
.ps2xml Windows PowerShell Display configuration file
.psc1 Windows PowerShell Console file
.psc2 Windows PowerShell Console file
.pst Microsoft Outlook personal folder file
.reg Registration entries
.rem ACT! database maintenance file
.scf Windows Explorer command file
.scr Screen saver
.sct Script file
.shb Windows shortcut
.shs Shell Scrap object
.shtm HTML file that contains server-side directives
.shtml HTML file that contains server-side directives
.soap Simple Object Access Protocol file
.stm HTML file that contains server-side directives
.svc Windows Communication Foundation (WCF) service file
.url Uniform Resource Locator (Internet shortcut)
.vb Microsoft Visual Basic Scripting Edition (VBScript) file
.vbe VBScript Encoded Script file
.vbs VBScript file
.vsix Visual Studio Extension
.ws Windows Script file
.wsc Windows Script Component
.wsf Windows Script file
.wsh Windows Script Host settings file
.xamlx Visual Studio Workflow service file


A word of warning

Your IT department can also limit which files types can be uploaded. If there is some security concern that they feel necessitates the ability to stop, say, ZIP files from being uploaded, they can do that in SharePoint 2013. So if you’re hitting an upload error and you’re not seeing the items from the full list, check with your SharePoint folks first to make sure they didn’t do it. And if they did, ask why. Maybe you can request an exception or ask them to reconsider the policy. Sometimes we all get spanked for the stupidity of one person, and that’s not always productive.

File type and naming restrictions

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