You have bigger issues than this form error. That table is not set up properly. You should not be storing data in field names, you are doing this in by numerating your fields (1, 2, 3, etc.) and with prefixes (before/after). That data, if necessary should be stored in fields in the table, not in field names of the table. This is how the above table should be set up:
picID, autonumber, primary key
RiskIDpic, short text, my guess is foreign key, this remains
picBefore, Yes/No, Yes means it is before, no means it is after
picPath, short text, this will hold the path
picName, short text, this will hold the name
picNumber, number, this will hold the number
My guess is that picNumber may not even be necessary because you just added the numbers as a way to differentiate all those fields you had in your table. But if it is, then keep picNumber. Then with that table, to add 3 pics you would add 3 records--one for each, you wouldn't add just one record for each RiskID that held 3 pics.
That's the way that table should be set up. The form for it would then be a simple subform which would allow you to enter all that data.