Category: Authentication

SharePoint: Common NTLM Authentication Issues, aka: Consider Ditching NTLM

Update 4/1/22:¬†Added Important note to Issues #2 and #6 Update 1/26/21: Added Issue #7 NTLM authentication is not great. It’s not the fastest. In most cases, that honor would go to Kerberos. It’s not the most secure. Again, Kerberos. It’s not all that flexible. For example, it doesn’t work well for extranets or anything cross-firewall.

SharePoint: SAML and FBA authentication fail from Word, Excel, Outlook, etc

Consider the following scenario: You have a SharePoint web application that uses Trusted Provider (SAML) authentication. When trying to open a Microsoft Office (Word, Excel, PowerPoint, etc) document from a SharePoint library, the Office app pops up a dialog with a “Sorry, something went wrong” error: Outlook calendar sync behavior: Users have SharePoint calendars that

Kerberos – KRB_AP_ERR_MODIFIED is not always an SPN problem

TLDR: This can also be caused by a mismatch in security policy “Network Security: Configure encryption types allowed for Kerberos“. ¬† Consider the following scenario: You have a web site set up to use Kerberos authentication. It doesn’t matter what kind of site, but we’ll say it’s a SharePoint site, since that’s the theme around

SharePoint: Users intermittently notice they are logged in as someone else

Problem: Intermittently users notice that they have automatically been logged in as a different user. For example, while browsing, you look in the upper right-hand corner of the page and see another users display name listed there. Clicking around more may result in switching back to yourself, or switching to another user altogether. Possible Causes:

SharePoint: Quick Troubleshooting Tip: Add the Account column to User Information List

Often while troubleshooting authentication or permission problems, you need to see the actual account name for the user or group added to permissions. This is particularly important in SAML / Trusted Provider authentication because the way the claim is being passed in the SAML assertion must match exactly with the way claim has been added

Keeping SharePoint happy during your domain migration

We’ve seen a few of different problems occur in SharePoint (2013, 2016, 2019) when users are being migrated from one domain to another. They usually come up in one of the following areas: People Picker People Picker may show either or both accounts depending on which domain SharePoint is in, and how PP is configured

SharePoint 2016, 2019, Subscription Edition: Configure the SSRS Report Viewer web part

Starting with SQL Server 2017, there’s only one installation mode for Reporting Services: Native mode. As such, the SharePoint integration with SQL Server Reporting Services (SSRS) is pretty much limited to getting the Report Viewer web part to work. Installing SharePoint, SQL and SSRS are beyond the scope of this post, so let’s pretend you