Solution : https://service.sap.com/sap/support/notes/603828 (SAP Service marketplace login required)
Key words : 
backward scheduling performance improves, /apoopt/dps/bin directory, recent microsoft runtime dlls, /apoopt/ctm/bin    dsoptsvr, /apoopt/dps/bin    mmpopsvr, /apoopt/mmp/bin    seqopsvr, /apoopt/seq/bin    snpopsvr, /apoopt/vsr/bin    cplex, /apoopt/snp/bin directory, /apoopt/mmp/bin optimizer
Related Notes : 
       
| 1047397 | SCM 4.0 Optimizer Support Package 21 | 
| 992496 | SCM 4.0 Optimizer Support Package 20 | 
| 945292 | SCM 4.0 Optimizer Support Package 19 | 
| 892151 | SCM 4.0 APO Optimizer Support Package 18 | 
| 869566 | SCM 4.0 APO Optimizer Support Package 17 | 
| 846382 | SCM 4.0 APO Support Package Optimizer 16 | 
| 821845 | SCM 4.0 APO Optimizer Support Package 15 | 
| 813691 | OPT_VSR_MSG201 - Error when setting up model | 
| 796783 | SCM 4.0 APO Optimizer Support Package 14 | 
| 772285 | SCM 4.0 APO Optimizer Support Package 13 | 
| 746473 | SCM 4.0 APO Optimizer Support Package 12 | 
| 743391 | SAP SCM 4.0 SP stack 07/2004: Release & information note | 
| 729776 | TP/VS Optimizer ignores free transportation resources | 
| 722516 | Optimizers do not start - message: Unable To Locate DLL | 
| 722062 | SAP SCM 4.0 SP stack 04/2004: Release & information note | 
| 719670 | SCM 4.0 APO Optimizer Support Package 11 | 
| 711292 | SAP SCM 4.0 SP stack 03/2004: Release & information note | 
| 703652 | SCM 4.0 APO Optimizer Support Package 10 | 
| 696859 | SAP SCM 4.0 SP stack 02/2004: Release & information note | 
| 694509 | SCM 4.0 APO Optimizer Support Package 09 | 
| 689455 | SAP SCM 4.0 SP08: Release and information note | 
| 685225 | SCM 4.0 APO Optimizer Support Package 08 | 
| 678512 | SCM 4.0 APO Optimizer Support Package 07 | 
| 677385 | SAP SCM 4.0 SP07: SAP SCM BASIS 4.0 (SAPK-40007INSCMBASIS) | 
| 669817 | SAP SCM 4.0 SP06: Release and information note | 
| 666945 | SCM 4.0 APO Optimizer Support Package 06 | 
| 664596 | SAP SCM 4.0 SP05: Release and information note | 
| 661488 | SCM 4.0 APO Optimizer Support Package 05 | 
| 655144 | SAP SCM 4.0 SP04: Release and information note | 
| 650869 | SCM 4.0 APO Optimizer Support Package 04 | 
| 643746 | SCM 4.0 APO Optimizer Support Package 03 | 
| 641751 | SAP SCM 4.0 SP03: Release and information note | 
| 639500 | SCM Support Package 02 for SAP SCM Release 4.0 | 
| 636683 | LP procedure: No capacity utilization | 
| 633093 | SCM Release 4.0 (installation/upgrade - delivery status) | 
| 632054 | SCM 4.0 Optimizer Support Package 02 | 
| 625782 | APO 4.0 SP0: PP/DS Optimizer cannot be executed | 
| 624947 | SCM 4.0 Optimizer Support Package 01 | 
| 621757 | SCM Support Packages 01 for SAP SCM Release 4.0 | 
| 605118 | SAP APO Optimizer Installation for SAP SCM 4.0 |