Article - CS350729
Unable to establish OPC DA communication after installing Microsoft DCOM Hardening patches (CVE-2021-26414) with PTC Kepware Products
Modified: 16-Oct-2025
Applies To
- ThingWorx Kepware Server (legacy) 8.0 to 6.17
- Kepware Server (formerly KEPServerEX) 5.20.396.0 to 6.17
Description
- Will Microsoft's phased rollout of tightened DCOM security impact KEPServerEX?
- Do installation of Microsoft Windows updates on OPC servers, which will include Microsoft DCOM Hardening patches (CVE-2021-26414 effects DCOM Hardening
- Effect of the Microsoft DCOM update on KEPServerEX communications
- Will the DCOM updates impact OPC UA/DA connections or any other protocols?
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