Error message : collect2.exe: error: ld returned 1 exit status (teensy 3.5)

Hello Folks,
when i try to compile my code i get this error message:
C:\Users***\AppData\Local\Temp\arduino_build_484030/core\core.a(main.cpp.o): In function `main’:

C:\Program Files (x86)\Arduino\hardware\teensy\avr\cores\teensy3/main.cpp:51: undefined reference to `setup’

collect2.exe: error: ld returned 1 exit status

Its a code for a Midi Sequencer (Hardware) with a Teensy 3.5. Everything is wired correctliy, this is the second version of my code, when i compile my old version everything ist working fine.

I am not sure which part of the code will make sense to post here, so i put the whole thing in the attachment, and here is the “setup” part of my code (please dont wonder, its not finished yet, with the compiler i just want to check if everything ist like it should be in this status of the code)

I hope someone has an advice for me. thank you for your time

cheers BoOah

void Setup(){
Serial.begin (31250);

//MCP23017 Starts
mcp1.begin(0); // Start MCP 1 on Hardware address 0x20
mcp2.begin(1); // Start MCP 2
mcp3.begin(2); // Start MCP 3
mcp4.begin(3); // Start MCP 4

//Main Toggle SWITCHES
// pinmode
pinMode(MainHeadMode[0], INPUT_PULLUP);
pinMode(MainHeadMode[1], INPUT_PULLUP);
// switch pinmode
pinMode(MainHeadSideMode[0], INPUT_PULLUP);
pinMode(MainHeadSideMode[1], INPUT_PULLUP);
//MainSubMode ToggleSwitch pinmode
pinMode(MainSubMode[0], INPUT_PULLUP);
pinMode(MainSubMode[1], INPUT_PULLUP);
// Pullup
digitalWrite(MainHeadMode[0], HIGH);
digitalWrite(MainHeadMode[1], HIGH);
//Main Head Sub (Main Mode real sub switch)
digitalWrite(MainHeadSideMode[0], HIGH);
digitalWrite(MainHeadSideMode[1], HIGH);
//MainSubMode Pullup
digitalWrite(MainSubMode[0], HIGH);
digitalWrite(MainSubMode[1], HIGH);

//Push Buttons Main Pin Modes
mcp2.pinMode(MenuButtons[0], INPUT);
mcp2.pinMode(MenuButtons[1], INPUT);
//Cherry Keys
mcp2.pinMode(CherryPins[0], INPUT);
mcp2.pinMode(CherryPins[1], INPUT);
mcp2.pinMode(CherryPins[2], INPUT);
mcp2.pinMode(CherryPins[3], INPUT);
mcp2.pinMode(CherryPins[4], INPUT);
mcp2.pinMode(MasterPushButtonPin, INPUT);
//Push Button Main Pullups
// MenuButtons pullup
mcp2.pullUp(MenuButtons[0], HIGH);
mcp2.pullUp(MenuButtons[1], HIGH);
// cherrykey
mcp2.pullUp(CherryPins[0], HIGH);
mcp2.pullUp(CherryPins[1], HIGH);
mcp2.pullUp(CherryPins[2], HIGH);
mcp2.pullUp(CherryPins[3], HIGH);
mcp2.pullUp(CherryPins[4], HIGH);
mcp2.pullUp(MasterPushButtonPin, HIGH);

//LEd Main pinmode
pinMode(ledMainGreen[0], OUTPUT);
pinMode(ledMainGreen[1], OUTPUT);
pinMode(ledMainRed[0], OUTPUT);
pinMode(ledMainRed[1], OUTPUT);
//LEd Main set default
digitalWrite(ledMainGreen[0], LOW);
digitalWrite(ledMainGreen[1], LOW);
digitalWrite(ledMainRed[0], LOW);
digitalWrite(ledMainRed[1], LOW);

//FSRs & SOFTPOTS ((rename later))
pinMode(FSR0PIN, INPUT);
pinMode(FSR1PIN, INPUT);
pinMode(FSR2PIN, INPUT);
pinMode(FSR3PIN, INPUT);
pinMode(FSR4PIN, INPUT);
pinMode(FSR5PIN, INPUT);

//bounce libary for Encoder Push
for (int i = 0; i < NUM_ENC_BUTTONS; i++) {
buttons.attach( ENC_PUSH_PINS , INPUT_PULLUP ); //setup the bounce instance for the current button
_ buttons*.interval(25); // interval in ms*
* }
//Midi Setup*
* // USB.Midi Callbacks*
* usbMIDI.setHandleNoteOn(handleNoteOn); // Put only the name of the function*
* usbMIDI.setHandleNoteOff(handleNoteOff);
usbMIDI.setHandlePitchChange(myPitchChange); //put in later*
* //usb midi clock In*
* usbMIDI.setHandleClock(myClock);
// Initiate MIDI communications, listen to all channels*
* //Midi SERIAL Callbacks*
* MIDI.setHandleNoteOn(handleDINNoteOn);
MIDI.setHandlePitchBend(myDINPitchBend); //put in later*
* MIDI.setHandleClock(handleClock);
TS Midi Merger v0.ino (22.9 KB)*_

“Setup” != “setup”

oh man... good hint. soooo any advice what i can do?