What are the specs of your import table, what is your VI definition and what version of Sage are you presently using?

I'm running a setup that existed before I started using Sage and I'm not certain what they've set up.  Using Sage 100.  This issue was something going on before I started and just never got remedied. 

Interesting, but not helpful at all.  I assumed it was Sage 100 since you are in Sage 100 forum.  What version of Sage 100 are you on?  Have you reached out to your reseller for their assistance since you are uncertain of the set up?  This is the best way forward to the root cause.

Steps to get to Visual Integrator (VI) and create a import job

1. Open Modules, Visual Integrator, Mainmenu, Import Job Maintenance
2. Enter the name of the job in Job Name field
3. Select the table AP_InvoiceHeader in the Table Name field
4. Click Accept
5. Click Yes to confirm this is a new job
6. Select the Data tab
7. The import should contain the following fields on the Data tab in this exact order:
   1. H.BatchNo (only required if Batch Entry is enabled in Accounts Payable Options
   2. H.APDivisionNo
   3. H.VendorNo
   4. H.InvoiceNo
   5. H.Comment
   6. H.InvoiceDate
   7. H.InvoiceDueDate
   8. L.AccountKey
   9. L.DistributionAmt
   10. L.CommentText
8. Click Accept and click Yes to execute the job
9. Click the Browse button to browse to the sourcefile to be used for the import job
10. Click Accept to run the import job and click Yes to confirm it is importing into the correct company