From the SDFS file, the 6 and 2 from the generated errors.
CE_INIT_ERROR Con 6 ' An initialization error has occured
sdcCardNotInitFailure Con 2

From section 10.3 18F4550 data sheet.
On a Power-on Reset, these pins, except
RC4 and RC5, are configured as digital
inputs. To use pins RC4 and RC5 as digi-
tal inputs, the USB module must be dis-
abled (UCON<3> = 0) and the on-chip
USB transceiver must be disabled
(UCFG<3> = 1).
And do you have the Capture / Compare turned off for PORTC?