Admins relying on **WUSA**, a built-in command-line tool for deploying Microsoft Standalone Update (.msu) files, have encountered `ERROR_BAD_PATHNAME` when attempting to install updates from network shares containing multiple .msu files. This issue, first acknowledged by **Microsoft** in August 2025, specifically affected updates released from May 28, 2025 (**KB5058499**) onwards. Initially, **Microsoft** deployed a **Known Issue Rollback Group Policy** in September 2025 to mitigate the problem for home and non-managed business devices. ## Fixed in June 2026 Cumulative Updates The comprehensive fix for this bug has now been integrated into the June 2026 Patch Tuesday cumulative updates. Affected systems can find the resolution in **KB5079391** for **Windows 11** and **KB5094125** for **Windows Server 2025**. For those still encountering the issue with older updates, **Microsoft** advises a workaround: saving the .msu files locally on the device and installing them from that location. Additionally, a brief 15-minute wait after installing an .msu file via **WUSA** and restarting Windows is recommended before checking the Update History page in Settings to ensure proper status indication. This resolution follows a series of other update-related fixes from **Microsoft**. In April 2025, an issue preventing enterprise customers from installing April 2025 security updates via **Windows Server Update Services (WSUS)** was addressed. An identical bug causing August 2025 **Windows 11** updates to fail with `0x80240069` errors was also resolved. Furthermore, **Microsoft** recently cautioned users about potential difficulties installing the latest monthly updates on some **Windows** devices upgraded to **Windows 11 24H2** or **25H2**.