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The ".maxUploadFileSize" property defined in &ltBC_HOME>\configserver\webapps\BusinessConnect\WEB-INF\configuration.properties specifies this limit.

.maxUploadFileSize=20960000

This is set to 20MB by default, increasing this property value (to 40MB for example) will help you upload larger files into BusinessConnect repository through the Configuration GUI.

NOTE: Please check with TIBCO Support before changing the above property, as loading very large files into the repository have been known to cause repository corruption. Also, there should be sufficient physical memory and JVM heap available for the repository server to upload very large files.