UTStarcom PPC-6700 / XV-6700 / HTC Apache

I have found that on this device many of my email attachments I cannot open. the phone cannot recognize the file when I open it. Is there any sort of application that would help the phone to recognize the file. I was reading up on Resco Explorer. If anyone can help me out in answering if this would be a good program for me or if not then what sort of program would be?thank you