@Carolyn Schroeder Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
Based on the error message : This is due to closing the window while an update is downloading or Application Insight package issue.
Go to this folder: C:\Users\<yourusername>\AppData\Roaming\StorageExplorer
Use notepad to edit settings.json, modify this “application.other.enableAppInsightsDiskRetryCache” to false.
If this property is not there, just add it to the json.
Save the file, restart Storage Explorer. The error dialog should be gone.
Make sure you're running the latest version of Storage Explorer.
Please let us know if you have any further queries. I’m happy to assist you further.
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