# WAGO E!Cockpit error Unresolved reference: 'FUIODRVCALCULATESLOTNUMBER' **URL:** \ **Category:** CODESYS\ **Tags:** ecockpit\ **Created:** [October 19, 2024, 11:40am UTC](https://www.wago.community/t/wago-e-cockpit-error-unresolved-reference-fuiodrvcalculateslotnumber/1261 "2024-10-19T11:40:18Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Jaba](https://avatars.discourse-cdn.com/v4/letter/j/6de8d8/32.png) [@Jaba](https://www.wago.community/u/Jaba)\ **Post date:** [October 19, 2024, 11:40am UTC](https://www.wago.community/t/wago-e-cockpit-error-unresolved-reference-fuiodrvcalculateslotnumber/1261/1 "2024-10-19T11:40:18Z")
Hello, "The error 'Unresolved reference: ‘FUIODRVCALCULATESLOTNUMBER’ persists. In analyzing the runtime.log, I received the following text:" Oct 19 15:34:11 localhost codesys3: CM DEBUG Failed to resolve FUIODRVCALCULATESLOTNUMBER Oct 19 15:34:11 localhost codesys3: CmpApp DEBUG Could not link external function FUIODRVCALCULATESLOTNUMBER ![Screenshot 2024-10-19 133828](https://us1.discourse-cdn.com/flex016/uploads/wago/original/1X/5c1afc5820154fb16ae1d9682bfc4f622d6ea3c0.jpeg) Does anybody have a clue of what is wrong? e!COCKPIT 1.11.3.1 Device Description 1.5.17.8 Firmware: FW: 03.10.10(22) Compiler: 3.5.17.30 Visualization Profile V3.5 SP17| PFC 100 750-8101 Thanks, Jaba ---
**Author:** ![WagoFlo](https://avatars.discourse-cdn.com/v4/letter/w/a6a055/32.png) [@WagoFlo](https://www.wago.community/u/WagoFlo)\ **Post date:** [October 21, 2024, 12:30pm UTC](https://www.wago.community/t/wago-e-cockpit-error-unresolved-reference-fuiodrvcalculateslotnumber/1261/2 "2024-10-21T12:30:00Z")
Hello Jaba, I also had this message, I had a problem with the KBUS libraries. Please try using the following versions. You may be using outdated or new library versions. FUIODRVCALCULATESLOTNUMBER is definitely related to the KBUS libraries. ![image](https://us1.discourse-cdn.com/flex016/uploads/wago/original/1X/7ac9a3930fcf24158903bac40883cc0517668f17.png)