The Properties file must reside on an NFS storage that is accessible by the platform pod. 

If you are using characters encoded with something other than iso-8859-1 in your property file for External References, the property file has to be converted to ASCII by using the Java tool native2ascii. For further information about using native2ascii, see the JDK product documentation.

If you have a large number of external references, this may impact the workflow startup time. It is therefore recommended that you do not exceed 1000 external references per file. If you require a number greater than 1000, split the references across multiple files and profiles.

When creating an External Reference File, it is important to keep in mind the format of the data you wish to specify. For example, consider an External Reference file (ExtRef.txt) below containing the following data with the value types list, map and string.

MY_STRING=A string value

MY_LIST=["Value 1","Value 2"]

MY_MAP={"Key 1":"Value 1","Key 2":"Value 2","Key 3":"Value 3"}

When this ExtRef.txt file is imported into the External Reference Profile, it will be displayed as shown below. As you can see, the Value Type for all keys are set as String by default.

To fix this, you will need to double-click on each Value Type and use the Edit External Reference Definition window to set the correct Value Type. Now you can observe that the Value is displayed correctly for all the Keys in your External Reference File.