SharePoint Designer Connection issue with SharePoint Online

[Sajith G H]

I am trying to access a SharePoint Online Site Collection using SharePoint Designer from Office 365 Tenant.SharePoint Designer shows an error Path does not exist.
If i try to connect another tenant using the same SharePoint Designer it connects. What could be the reason ?

[#2]

@Sajith G H SharePoint Designer likes to use cached credentials from Internet Explorer as opposed to the Office account you might be currently logged in as in your Office products.

Are you sure you are connecting through SharePoint Designer with the proper account for each tenant? 

[#3]

Hi @Sajith G H 

could you please give us more information about the URL / path?

Are you trying to connect to modern sites?

SharePoint online, in modern experience, doesn't support by default SharePoint Designer.

Please, verify NoScript setting for your site docs link, however, it is possible and supported to disable NoScript settings

Cheers,

Federico

[#4]

@Federico Porceddu 

I am trying to connect both modern & classic sites. Also  run the following command for the site collection

Set-SPOSite -Identity https://sitecollectionname.sharepoint.com -DenyAddAndCustomizePages 0

After enabling Apps that don't use modern authentication, the previous error is gone. Is this a correct  method ?

Still not able to access the site using SharePoint Designer

I tried with different users. Still the same issue. 

[#5]

@Sajith G H Did you try first logging in to Office 365 through Internet Explorer and having it remember your credentials, then try opening SharePoint Designer?

When consulting, I often had to use SharePoint Designer with different admin accounts for various Office 365/SharePoint Online tenants. Windows and Internet Explorer will store/cache your SharePoint Designer credentials. I often would get prompted over and over for login information if the stored credential didn't match the tenant site that I was trying to connect to.

The easiest workaround I found was this:

1. Close SharePoint Designer

2. Open Internet Explorer

3. Go to your SharePoint Site in Internet Explorer being sure to login with the correct account and selecting the option for Office 365/SharePoint to remember your login.

4. Open SharePoint Designer and go to the relevant SharePoint site.

[#6]

@Kevin McKeown 

Due to some reason, IE is having issue in Windows Server 2016. So we are using firefox as default browser. We can login into the SharePoint Online from the firefox browser. SharePoint Designer is unable to access.

[#7]

@Sajith G H 

I still think it has something to do with stored credentials. I would try going into the Credential Manager in Control Panel and removing anything Office 2013 related, then trying to open and login to SharePoint Designer again.

[#8]

Coming back after three years with nowadays findings:

1. enable custom script
2. enable access for apps for old auth method
3. remove credentials in Windows (credentials manager) related to office
4. put sharepoint online site link into sharepoint designer 2013 pop up window once you click on "open site"