Solution : https://service.sap.com/sap/support/notes/1796762 (SAP Service marketplace login required)
Key words : 
41  support packages & patches support package patchessoftware componentsupport packagepatch levelsap kernel 6, medium priority category program error validity software componentfrom rel, note / patchnote reasonfrom versionto versionnote solutionversionsupport packagethe table, customer component bc-sec-vir anti virus protection, notenote reasonfrom versionto versionnote solutionversionsupport package1640285 0 0 1796762 1, __%pdfstyle%__ / } symptom error message, components bc-sec security priority correction, - side effects notes / patches corrected, release information 639486   anti-virus protection, antivirus area 639486   anti-virus protection
Related Notes : 
       
| 1640285 | Determine MIME type with Virus Scan Interface | 
| 1796762 | NW-VSI 2.0: Error when loading external adapters | 
| 1883424 | NW-VSI 2.00: Release information | 
| 1494278 | NW-VSI: Summary of Virus Scan Adapter´s for SAP integration | 
| 817623 | Frequent questions about VSI in SAP applications | 
| 786179 | Data security products: Application in the antivirus area | 
| 639486 | Anti-virus protection within SAP applications (BC-SEC-VIR) |