QB Issue Resolution:

I haven’t done this but if you have selected assign check numbers, select all the bills then ok, assign a number at the first line entry, QB groups them as a single payment anyway.

Resolution for Issue 'I recently went from windows to mac and upgraded to 2014 version. how can i pay multiple invoices for one vendor and not have to re-enter the check # 2-10 times for the same payment' available: Yes (Solved).
Source: Intuit Community forum.

I recently went from windows to mac and upgraded to 2014 version. how can i pay multiple invoices for one vendor and not have to re-enter the check # 2-10 times for the same payment: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for Invoice
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