I think your URI is wrong.

Was doing a bit more snooping (as I'm not 100% familiar with how that works) and I THINK you are missing the URI...

My only comment on that is your last line: "and i.name in ('')".  that'll remove all of the indexes, no?
but the last_user_* columns can be interesting too.  I mean,...

Any update on this?

I am curious if you found a different solution to the problem that we didn't think of or if you just manually re-created all of...

Depending on how your relationship with your customers is, you could push back and tell the customer to provide the document in a specific format?

Failing that, you need...

I am willing to bet the drive is mapped at logon.
So when the service account runs the job, it is not mapped as the account doesn't initiate a logon.

As another thought, does inserting it into a temporary table have the same slowness as inserting into the a real table?

That is you indicated that this:

            
July 7, 2017 at 12:33 pm
            
#1950012

            
            
                                                
        

Adding to Theo Ekelmans's comment, I did do a little snooping to see how this could work and found this powershell module:
https://gallery.technet.microsoft.com/scriptcenter/2d191bcd-3308-4edd-9de2-88dff796b0bc

This would be using a...

how many indexes do you have on the table?

If there are a lot, maybe try disabling the indexes before you do the insert.  It may even be faster...

As a thought, are you sure you have the correct server name?

I see that you have a $servername variable and then a different value in your URI creation...