Say I want to make a Muffler[1]; Item ID #2504. When I use @produce 2504, the Muffler created is unslotted.
The only way I am able to slot a card (e.g. Raydric) in is by using @item2, in which case, the slots and card still don't show up. However, the name is Immune Muffler. (Not Immune Muffler[1] as it should be.)
I did a forum search and Riot suggested removing the itemslotable.txt file. After doing so, I still could not see slots.
Help? 
*EDIT: Wow, go me. I'm an idiot. Thanks yC. ^^;;;;;;;;;;;
There's something wrong with my client in which I don't always get the correct item. For example, I @item Dragon_Tail_Card, and I get a Cruiser Card instead. Same thing if I use the item ID# for Dragon Tail Card. Then, when I @item Cruiser_Card, an Unknown Item apple appears.
BUT!! Here's the catch. I had someone else create the item and it showed up as Dragon Tail Card. When they dropped it for me, I still saw Cruiser, but they saw Dragon Tail. THEN!! When I successfully slotted it into my Muffler[1], it became Cruiser Card Muffler [1]. But the other person saw it correctly as Bow-Master's Muffler.
And also, when the person dropped me items such as Stat foods, it showed up as random taming items. But, when I used them, it still gave me stat bonuses.
Soooooooooo, yeah. I'm really confused. Any solutions?
Thanks.

Um, another random question...what email address do I use to delete characters? The email address I used to sign up for this board keeps getting rejected when I try to delete. =/