in fpd26 we deleted index ,pack then made index again
but still have same error when using in vfp6
anybody have any ideas?

I had the same problem several months ago converting an application from 2.6 to VFP3 and later to VFP6. If you must run your application in 2.6 using VFP data, try a clone dummy table in 2.6 that imports data from VFP. The two formats don't work well together.