KEB0 - can't re-generate COPA DS using KEB0, 'Generate' grey out

We implemented COPA in BW 3.5 the old way using KEB0 and have re-generated several times before upgrade to BI7.0 and used KEB5 to transfer delta time stamp. This was working fine. That was before BI7.0 upgrade. Now I need to re-generate the COPA DS using KEB0 for another new KF and but the 'generate' option is grey out. How can I re-generate the COPA data source now? Please advise ASAP.

On ECC side, we have EHP4 FOR ERP6.0, PI_Basis is SAPK-70103INPIBASIS, SAP_BW is SAPKW70103; on BW side, it's EHP1 for NW 7.0. I have tried to seach OSS note invalid. I have also de-activated the old DS, delete it using KEB0, remove the delta queue from RSA7.

Thanks in advance,

Grace Hu

SAP BI Techincal Specialist