1. A scan server comprising: a creation unit configured to create instruction data for instructing scan setting and OCR preprocessing which should be performed by a scan device; a transmission unit configured to transmit the created instruction data to the scan device; a reception unit configured to receive, from the scan device, an OCR-preprocessed scan image which is acquired by performing the scan setting and the OCR preprocessing instructed by the instruction data in the scan device; and an OCR unit configured to perform an OCR processing on the received OCR-preprocessed scan image.