I came across this but can't remember where, I did however make a note of it just incase. Error 22:dashboard.xbe targets not found on the following directories e:\dash\default.xbe, e:\dashboard\default.xbe, e:evoxdash.xbe. Its an UnleashX dashboard skin made by sid, not an xbox error. Bad softmod error. Try using the game used to mod to get to the sid menu. Ftp into the xbox. Replace C with stock files from slayers. Or do the same with slayers.
Yep, It sounds like you have bad linux file. Then only way to fix it is to remove all linux file in C and E drive. Then reinstall ms dash on C. So you will have something like this: C:\fonts, audio, xodash, xboxdata, xboxdash.xbe, xbox.xtf, xbdash.xtf E:\UDATA and TDATA. They are empty folders. F:\empty