PROBLEM
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Getting “Unable to cast object of type system.net.filewebresponse to type system.net.httpwebresponse” error message in client side import scirpt

RESOLUTION
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The sdo package path has been specified as standard windows physical file format as “E:\folder\sdofilename.sdo”

ROOTCAUSE
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The SDAPI import method reads the sdo file path and it process afterward. It’s expecting a path format that compatible with HttpWebResponse. When we use x:// notation, .net might interpret it as a FileWebResponse and that’s could be what causes the InvalidCastException.