Win XP Service Pack 1- won't install

[jambo45]

Hi,
i could really use some help. I have got win xp sp 1 on disk and i wanna install it. But when i try to i keep getting an error saying that i need cryptographic something running on my computer. And thus i can;t get to install it. can anyone help.

AMD Athlon XP 1700+
GA7DX+ motherboard
256Mb DDR RAM
30GB Maxtor Hard drive
ASUS Geforce 4 Ti4200 128MB
Modem
LG DVD Drive
Floppy drive
Windows XP Home Edition OEM