Memory Checker detected 1 access violations

Hi,
Can somebody help me wit this error? Why does this error come?

CUDA Memory Checker detected 1 threads caused an access violation:
Launch Parameters
CUcontext = 01452de0
CUstream = 060480c8
CUmodule = 06237a28
CUfunction = 06ba67d8
FunctionName = _Z4HashPcS_i
GridId = 1
gridDim = {62,1,1}
blockDim = {32,1,1}
sharedSize = 1792
Parameters:
hash = 0x40ec0200 -1 ‘ÿ’
input = 0x40ec0000 97 ‘a’
length = 3
Parameters (raw):
0x40ec0000 0x40ec0200 0x00000003
GPU State:
Address Size Type Mem Block Thread blockIdx threadIdx PC Source

00000000 1 adr ld g 0 0 {0,0,0} {0,0,0} Z14stringtohex_BEPcS+0000d8 c:\users\s149709\documents\visual studio 2013\projects\4122014-new\hash.cu:365

Summary of access violations:
c:\users\s149709\documents\visual studio 2013\projects\4122014-new\hash.cu(365): error MemoryChecker: #misaligned=0 #invalidAddress=1

Memory Checker detected 1 access violations.
error = access violation on load (global memory)
gridid = 1
blockIdx = {0,0,0}
threadIdx = {0,0,0}
address = 0x00000000
accessSize = 1

Stepper Failed: Trying to step invalid warp.
Stepper Failed: Trying to step invalid warp.
CUDA grid launch failed: CUcontext: 21310944 CUmodule: 102988328 Function: _Z4HashPcS_i

Regards
Bhupesh