Problem with delayed effect of setting DenyAddAndCustomizePages to false on modern Sharepoint Online site

Some time ago we faced with the following problem: let’s say we have PowerShell script which does some actions on modern Sharepoint Online site collection. Among with other actions it sets property bag values on the root site of the target site collection:

Set-PnPPropertyBagValue -Key "Key" -Value "Value"

In order to do that (as well as to do other customizations on the modern site) you need to set DenyAddAndCustomizePages property to false on that site (see e.g. Access denied when try to delete folder in Modern Sharepoint site’s doclib). It can be done using the following PnP PowerShell cmdlet:

Set-PnPTenantSite -Url $url -NoScriptSite:$false

It returns control quite quickly. The problem however that on practice effect from setting DenyAddAndCustomizePages to false has delay. I.e. if you will try to set property bag value using cmdlet shown above immediately after you set DenyAddAndCustomizePages to false – there won’t be any errors but value won’t be really saved into property bag.

As workaround I’ve added 60 seconds delay to the script with UI indication (dots are printed to output each second until there won’t be 60 dots in line):

Write-Host "Wait some time before changes will take effect..."
$i = 0
do
{
	Write-Host "." -NoNewLine
	Start-Sleep -s 1
	$i++
}
while ($i -lt 60)
Write-Host

After this delay property bag values were saved successfully.

UnauthorizedAccessException when try to delete alert from Sharepoint site

If you try to delete alerts from the Sharepoint site programmatically:

SPWeb web = ...;
web.Alerts.Delete(alertId);

You may face with UnauthorizedAccessException:

<nativehr>0x80070005</nativehr><nativestack></nativestack>
    at Microsoft.SharePoint.SPGlobal.HandleUnauthorizedAccessException(UnauthorizedAccessException ex)
    at Microsoft.SharePoint.Library.SPRequest.DeleteSubscription(String bstrUrl, String bstrListName, String bstrSubId, Boolean bListItem, UInt32 ulItemId, Boolean bSiteAdmin, Int32 lUserId)
    at Microsoft.SharePoint.SPAlertCollection.Delete(Guid idAlert)

First thing to check is of course that account under which the code above is executed has all necessary permissions on the site. If this is the case but the problem is still there check that your site collection is not in readonly mode. You may do it using the following PowerShell command:

Get-SPSite -Id http://example.com | select ReadOnly,Readlocked,WriteLocked,LockIssue | ft -autosize

If site is in readonly mode result will look like this:

and if site is not readonly it will look like this:

You may unlock site collection using the following PowerShell command:

Set-SPSite -Id http://example.com -LockState Unlock

And set it to readonly mode like this:

Set-SPSite -Id http://example.com -LockState ReadOnly

Hope that this information will be helpful.

Using of relative and absolute urls when create Modern Sharepoint site via PnP PowerShell

Modern Team and Communication sites can be created through PnP PowerShell cmdlet New-PnPSite. Here are examples how you may create these sites:

Team: New-PnPSite -Type TeamSite -Title Test -Alias test
Communication: New-PnPSite -Type CommunicationSite -Title Test -Url https://{tenant}.sharepoint.com/sites/test

Note that for Team site we use Alias parameter while for Communication site we use Url. It is mandatory to use relative url when you create Team site and absolute url when you create Communication site. If you will try to create Team site with absolute url:

Team: New-PnPSite -Type TeamSite -Title Test -Alias https://{tenant}.sharepoint.com/sites/test

you will get the following error:

Invalid value specified for property 'mailNickname' of resource 'Group'.

And if you will try to create communication site with relative url:

Communication: New-PnPSite -Type CommunicationSite -Title Test -Url test

there will be another error:

This operation is not supported for a relative URI.

Hope that it will help someone.

Access denied when try to delete folder in Modern Sharepoint site’s doclib

Recently I faced with the following problem: when you create OTB Modern Team or Communication site (see How to create modern Team or Communication site in Sharepoint) you can create sub folders in document libraries, e.g. in Style library:

(BTW with modern experience currently it is possible to create sub folders of only first level. If you want to create sub folders of deeper levels you have to switch to classic experience and create sub folder from there)

However if you will try to delete this folder you will get the following error:

Sorry, something went wrong
The server has encountered the following error(s):
Test
Access denied. You do not have permission to perform this action or access this resource.

In order to avoid this error you need to enable customizations of pages and scripts on the site. You may do it with the following PowerShell command:

Connect-SPOService -Url https://{tenant}-admin.sharepoint.com
Set-SPOSite {url} -DenyAddAndCustomizePages 0

After that you will be able to delete sub folders in Style library doclib on the modern site.