An Error Has Been Signaled By The Protected Object Server File Synsoacc.dll [ LATEST ]

icacls C:\Windows\System32\synsoacc.dll /reset Temporarily uninstall any non-Microsoft antivirus or EDR software. Reboot into Safe Mode with Networking . If the error disappears in Safe Mode, the culprit is a third-party filter driver or security hook. Reinstall the security software but add an exclusion for C:\Windows\System32\synsoacc.dll and lsass.exe .

Open Regedit and navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NTDS\Parameters Ensure the Allowed Protection Levels value is not set to an invalid state. Then, download Process Monitor from Microsoft Sysinternals. Filter on Process Name containing lsass.exe and Path containing synsoacc.dll . Look for “ACCESS DENIED” results. Restore default permissions if necessary using icalcs : icacls C:\Windows\System32\synsoacc

Run the following from an admin command prompt: icacls C:\Windows\System32\synsoacc

w32tm /resync net time \\yourdomaincontroller /set Then verify the Kerberos ticket cache: icacls C:\Windows\System32\synsoacc