The long side of the trapezoid go on the back of the tablet.
The short side goes on the screen side.
It should slide in that was with only slight resistance.
Mark the back side of the plug with fingernail polish, "White Out", or paint, so you don't get it wrong.
Had mine about 3 weeks. Noticed the problem right away and was very careful. However, yesterday morning the plug would not go all the way in. I had not forced it but a couple times I started to plug it in upside down, felt the resistance, stopped, turned the plug around and then it went in. Yesterday it simply would not go in (it was turned correctly). Could not charge tablet and could not reset to factory settings. Had to use CCleaner to wipe it clean. Returned it to Costco and got a full refund. Thank you Costco.
The paint is a good idea, but you're just prolonging the inevitable. Sooner or later, you're going to plug it in upside-down and destroy it. It should not be possible to do this. Each and every one of these Dell Venue 8 Pro devices is doomed to an early extinction because of this. It's a colossal design failure. Dell needs to recall them all.
I've painted nearly the entire back of every plug I use with this thing white. I'll never plug in it backwards. But I do think that someone's head should roll at Dell for making such a terrible decision. I wouldn't be surprised at all if a large percentage of these get broken and returned. It's going to be a huge loss for Dell.
Unless Dell has warehouses full of these they'll be doing a "minor" fix to new systems based on their returns.
If they do this we'll all just return them in the fall (just before the end of the warranty) and get new ones with the plug problem fixed. Those who don't use there tablets much will keep the old connectors.
Does Dell monitor these forums?
Been looking around, ie Best Buy, Frys, Dell website, eBay, and because I really like this thing while I had it, I just might buy another one from Costco. If the USB receptacle fails again (I'll have 90 days to use it), I'll just take it back.