Excel operations do not work due to "access denied"

Currently I am having an issue regarding the “Get cell value”-action. I have downloaded the Excel Operations addon and installed the latest agent but as soon as I try to get the cell value with given parameters “SheetName”, “ColumnNumber” etc. I get the error:

java.security.AccessControlException: access denied (“java.lang.RuntimePermission” “getClassLoader”)

Can somebody assist?

Thanks in advance!