No accounting entry generated

Hi Experts,

We have created one tax code O8 in FTXP and assigned GL in OB40 but during sales invoicing it is giving error that no accounting entry generated(Message no. VF050) and also when we are booking customer sales invoice in FB70 with the same tax code O8 we are getting error that Tax code O8 country IN does not exist in procedure ZTAXIN. We have done all permutation and Combination but still not able to solve this error.Do we have to assign gl in VKOA and where do we assign ZTAXIN to Tax code is there any tcode for it.Kindly help me to solve this errror.

Sonal