POS System Document Not Working After Windows 11 Security Updates

The POS document fails only while KB5120708 or KB5122385 is installed and works after removal. Both are cumulative .NET Framework updates, so a .NET-based POS application or document component may be exposing a compatibility defect. Microsoft currently lists no known issue for KB5122385, so the update alone does not establish a confirmed Windows defect. Reinstall the updates on one test device, reproduce once, and record the exact application error, Event Viewer Application log, POS version, .NET runtime, image paths, and whether a simple local image opens. Test a copy whose images are stored in a non-root folder such as C:\POSData, with normal user permissions. Install the POS vendor’s latest build and the newest Windows cumulative update. Do not leave security updates permanently removed. If the failure remains, open vendor and Microsoft support cases with the comparison logs; only they can determine which component requires correction.