Error in MIRO

When i am using the transaction MIRO..............I am getting below error. Please give the solution for this error. I am giving the suggestions given by R/3 system also.

Error: *No posting rules exist for account key*

Suggestions:

No posting rules exist for account key

Message no. FF714

Diagnosis

No posting rules have been defined for the account key in the tax table in table T007B.

Procedure

Change the tax table, enter an account key already defined for the transaction in question or define the posting rules for a new account key in table T007B.

Regards

Ganesh