Due to my laziness, I created a created a dataset with 9800 symbols. The GUI won't let me save that many so I open the xml file and saved it. When the nightly update hits,for some reason the fidelity daily data with 9000+ symbol does not update automatically. However, if I highlight it and hit update price, it does go and update.

Any idea on how to get around this issue ? I copy some other code from other threads to dynamically update my datasubset so I can do a big scan and write all my symbols to a daily and 15 min dataset and run the strategy monitor after a restart without doing much manual work.

Manually editing the XML file is not a supported use case. The Fidelity provider will not let you create a DataSet which contain more than 32767 chars (~6500 symbols). To get around the issue, break your symbol universe in two DataSets. "Update all data" should work, and to combine them back you might give this 3rd party extension a try (this is not supported either):

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