[Note: This is all on sysNAND] OK so I had haxchi channel working nicely (using Dr. Kawashima). I decided to install some eShop games and forgot I had and eShop download of Dr. K also on my SD. So I sig patched the nand and then started WUP, selected all and boom, error. Can't remember the error it said on WUP (I didn't write it down, but said something about sig patching). No big deal I thought. Delete, go to eShop and re-down. ERROR. 105-3687. Restarted, tried again. Same error. I read a lot of useless posts on gba but I remember one guy having a similar issue and he fixed it by deleting the tik [yes, that was an intentional dig at shit posters ]. They are stored here: /vol/system_slc/rights/ticket/apps/ In my particular case it was then in folder /0005/0000001d.tik I know this because I had already run tik2sd and had a copy of all my tiks. I thought I could just re-up my original tik but then I thought that would change the permissions on the file (which I can also change but...well, six of one, half a dozen of the other). So I deleted the tik using wupclient, rebooted unit, went to eShop and re-downloaded & installed game. FIXED. Great. Hope it might help anyone else if they have the same error because there is nothing about this error on the internet I could find. Obviously, be careful if you are not good with wupclient and don't just delete random shit!