Um, I bet that the real problem is one of shooter technique.

Possibility One:
Your thumb is contacting the pistol's slide-lock lever, and pushing upward on it as you fire, or as the gun recoils.
If your thumb, or any finger, contacts the slide lock, it will do its assigned job—even if you don't want it to.
Find a way to grip the gun without contacting the slide lock in any way. This should solve your problem.

Possibility Two:
If you are not holding this little gun with a death-grip, your hands and arms are absorbing some of the recoil force that the pistol needs, to operate correctly.
Your grip needs to be ultra-firm, and your arms need to be locked. Do that as well, and your problems will very likely disappear.

It's very easy to blame the gun, but you must also carefully assess your own technique as well.

^ Agree...

The Solo is very finicky ammo wise and you can't "limp wrist" it while shooting.

You didn't reassemble the gun correctly or it was assemble incorrectly. Retaining spring was most likely missed. Go to the Kimber website and look at the videos under the support section. It'll show you what was missed.
Kimber America | Videos featuring Kimber America Pistols and Rifles

Check out page 37 in the manual:

Step 8 in resembling the gun:

Press slide stop inward until fully seated and
release slide (Figure 21/1d and 2d). Be certain
that the slide stop has picked up the retention
spring located on the frame (Figure 21/3d).
Failure to install the slide stop below the
spring will cause the slide to lock open while
firing.

And for the record....my Solo CDP has been flawless with zero FTF or FTE's.

Glad you got a good one, she took her's back today to the place she purchased it and they fired it as well with 124gr and 147gr and yep they were in disbelief, however they did manage to get three rounds fired thru it with the 147gr. It's on it's merry way back to Kimber, lets see what they have to say about it. I'll keep you posted.

Originally Posted by DoingOK

You didn't reassemble the gun correctly or it was assemble incorrectly. Retaining spring was most likely missed. Go to the Kimber website and look at the videos under the support section. It'll show you what was missed.
Kimber America | Videos featuring Kimber America Pistols and Rifles

Check out page 37 in the manual:

Step 8 in resembling the gun:

Press slide stop inward until fully seated and
release slide (Figure 21/1d and 2d). Be certain
that the slide stop has picked up the retention
spring located on the frame (Figure 21/3d).
Failure to install the slide stop below the
spring will cause the slide to lock open while
firing.

And for the record....my Solo CDP has been flawless with zero FTF or FTE's.

I recently (finally!!!) received my Solo CDP. First I cleaned and lubed and reassembled it. Then I loaded with the Remington Golden Saber 147 grain. It locked back as unloaded each time. Then I looked closely at the Kimber YouTube on reassembly and saw that I had not locked the pin under the spring. Re-assembled and it has worked flawlessly for 100 rounds using also, Golded Saber 124 grain, Hornady Critical Defense 135 grain and, at half the price, Hornady 135 Training rounds. All worked flawlessly. Just for sniffs and giggles, I tried some 115 grain Remington non-hollow point and it was a case of every other FTE. The more I use the pistol ( with the right ammo), the more I like it.

Did they fire it with hollow point? It seems to favor that. Perhaps because the recoil spring is sp strong, because of the short barrel, it needs just the right amount of energy going back to function properly. Maybe it is the price paid for having the smallest 9mm?

Out of 500+ rounds I've had 3 fte using cheap range ammo like it said not to. If works perfectly with 124 grain brazer brass I just tryed the other stuff to see what it would do. All in all I love my kimber solo

Originally Posted by androw

Out of 500+ rounds I've had 3 fte using cheap range ammo like it said not to. If works perfectly with 124 grain brazer brass I just tryed the other stuff to see what it would do. All in all I love my kimber solo

I have had my Kimber Solo LG about 2 months. Due to the ammo shortage I had to start off with 115 grain Independence ammo.

First I cleaned and lubed the gun, then went to the range. Normally, I would have waited for warmer weather, but wanting to know how the Kimber would perform, I had to go... it was cold 28 degrees with about a 20 mph wind. Was even more frustrated because I had to shoot at the 50 FT range... Loaded up five, took my stance and fired 5 shots... all in the six inch orange!!! To make a long story short 100 rounds later all rounds are in an 8" ring with no failure to feed or fire.

#1 amazed at the accuracy
#2 totally happy with the function of the pistol

The next weekend I had found some Lawmen 124 grain shot 23 of them without issue (Now officially broken in according to Kimber) Then followed up with 150 rounds of bagged 115 grain reloads bought from the gun show. still perfect now at 273 rounds!

Saturday, put another 100 of 115 grain Independence through the Solo.

I had heard about limp wristing being a factor... So I grasped it very loosely the only grip being the pressure of the trigger pulling to the web of my hand, three shots three BE with the 3 bullet holes touching at 50 feet ... wow!!! During this round the range officer and 4 fellow shooters took their turns with the Solo.
So with 373 rounds fired there has not been one malfunction of any type!!!

My issue is I am down to my last box of ammo!!!