Why isn't this working...?

Yes, I am trying to force signed into unsigned.
By dereferencing the LHS I hope to accomplish the conversion.
It's the segmentation fault that concerns me.
I'm curious to know what bounds of programming I've exceeded?
Thanks in advance...Dave++

Code:
unsigned long* scalerData[COUNTERS];
long Data;
...
call function(){
 for(int i=0; i<COUNTERS; i++){
    this->Read32Counter(i, &Data);  // Read32Counter(int, long*)
    *this->scalerData[i] = Data;       // *this->... causes segmentation fault                           
    // this->scalerData[i] = &Data;   // error: pointers of non-equal type