Out of the box, if you upload a document to SharePoint and tag metadata to it, that data is attached to the document properties. This is the case for most all column types you create in a library, and on random occasions, Document IDs are copied.
If you are working with SharePoint on-prem you can disable this functionality at the SPWeb level, but that’s not the case with SharePoint Online.
on-prem code example:
$web = $ctx.Web
$web.ParserEnabled=$false
$web.Update()
Example of what I was seeing in my sample library:
Create a new library titled DocLib
Added a text column titled TacoFiller
Uploaded an Excel file, then populate TacoFiller with the word Beans
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Downloaded the file and look at the properties.
File –> Info –> All Properties (Excel o365)
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Notice that property TacoFiller is set to Beans.
Create a local copy of the file, then upload it to DocLib.
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SharePoint has read the TacoFiller property from the Excel file and applied the data to the column in the library.
Short of doing a document migration, I have NO idea why you’d want this enabled out of the box. If anything, this should be disabled, then allow admins to enable as needed. /rant
TL;DR / how-to disable this functionality:
First, you can only disable this at the library level!
#Load SharePoint CSOM Assemblies
Add-Type -Path "C:\Code\DLL\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Code\DLL\Microsoft.SharePoint.Client.Runtime.dll"
#Config Parameters
$SiteURL= "https://YourSite.sharepoint.com/sites/spdev/testsite"
$ListName="DocLib"
#Get Credentials to connect
$Cred = Get-Credential
Try {
#Setup the context
$Ctx = New-Object Microsoft.SharePoint.Client.ClientContext($SiteURL)
$Ctx.Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($Cred.UserName,$Cred.Password)
#get list sharepoint online powershell
$List=$Ctx.Web.Lists.GetByTitle($ListName)
$Ctx.Load($List)
$Ctx.ExecuteQuery()
Write-host "Parser Disabled value " $List.ParserDisabled
$List.ParserDisabled = $true
$List.Update()
$ctx.ExecuteQuery()
}
Catch {
write-host -f Red "Error:" $_.Exception.Message
}
A couple of notes about the script.
You can download the SharePoint DLLs from Microsoft: link
In my tenant, using Get-Credential requires that I use my company email address and an App Password. This may/not be the case with your tenant. App Password info: link
And… after running the script, upload another copy of the Excel file to the library.
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The TacoFiller property is no longer being extracted from the Excel file!
I’d like to thank Abhijit Rajurkar for helping with this!