My ignorant friend tries to put the number "5" in his calculator. Slot 5 is where his calculator was. It crashed the server.

Haha okay, Crash Report?

http://pastebin.com/bnFbkk6P

Erm okay, I'll have to look into this not 100%% sure why this is happening yet

I'm not too sure, but the calculator didn't like being put inside itself.

you put the calc in itself? i don't know the code but that indeed sounds like the best way to cause an infinite loop like this

I believe so. My friend said he tried to put "5" in the calculator. It seems to me like the calculator was probably in slot 5.

Confirmed. Took storage module and put it in slot 2. Then opened it and put slot 2 there. Luckily the result was only lost storage module not corrupted world (luckily? I believe I didn't put atomic multiplier in there...)

can't recreate this at all, I could get a calculator within a calculator within a calculator within a calculator

Hmm... I'll try to recreate it again today to see if there's anything else needed to recreate.

I have been able to reproduce it again today. I think you misunderstood my original comment. To reproduce, right-click to open the calculator interface (tested with the plain calculator) and click the number that corresponds with where the SAME calculator is on your hotbar. For example, I right click with slot 9 on my hotbar (the calculator), then I press "9" on my keyboard to put the item from slot 9 on my hotbar in to the calculator (also slot 9).

The problem is putting the SAME calculator inside itself.

And then server crashes and calculator vanishes. Same issue is with storage modules. Also I can say that neither TE satchels nor XU golden bag of holding nor MFR plastic bags don't have this issue, pressing number with them simply does nothing (can't say about AE portable cells).

Fixed in dev