Installing TIA Portal (e.g., V15, V17) alongside an older Step 7 V5.6 SP1 can cause registry conflicts.
The s7yomlr.dll file (or its variants like s7yomlra.dll for specific languages) should typically be located in: C:\Program Files\siemens\step7\s7bin . cannot find language resource file s7yomlr.dll
Siemens STEP 7 is highly sensitive to the operating system's regional settings. If your Windows display language or system locale is set to a region that the software package does not support, it will fail to look up the correct language resource file. Installing TIA Portal (e