On Acers you're right there is a configuration file called by Launch Manager that maps the specific Euro key. I guess this was a victim of the "clean up"
Download the file from Acer support here:
http://global-download.acer.com/GDFiles/Application/LaunchManager/LM_Dirtek_2.0.0.119_Vistax86x64.zip?acerid=633639037866615069&Step1=Notebook&Step2=Aspire&Step3=Aspire 5920&OS=V10&LC=en&SC=EMEA_
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