This property controls how long temporary files should be kept before application automatically deleting them. When you are using custom AsyncUploadConfiguration, TemporaryFileExpiration property reads value from TimeToLive property.
After the Default Upload Configuration is created TTL is send to the client together with all properties from AsyncUploadConfiguration. Then the user selects file for uploading and the configuration is transferred from the client to the upload handler. The TTL starts right after the file is uploaded.
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