Symptoms

Upload Excel with SmartForm Upload control is not working, it throws the following error:
"The file could not be uploaded. Unforseen error occured on the file upload, contact your Administrator."
 

Diagnoses

This error occurs in most cases as a result of timeout.
 

Resolution

The following can be done to resolve the error:
1). Firstly, make a backup of the Smartforms Runtime's web.config file
2).Then make the following modifications in the file:
set executionTimeout="9999" AND maxRequestLength="2097151" in <httpRuntime ... /> Tag.
3). Perform an IISRESET after the change.