Unhandled exception at 0x0110101a in IndirectoffsetAddress.exe: 0xC0000005: Access violation writing location 0x0110004d

I had a problem with assembly code: Here is my code:

.data
m byte "ManshaDar"

.code
main proc
mov eax, offset m
mov al, [eax]
mov ah, [eax+2]
mov [eax], ah
mov [eax+2], al
main endp
end main

Assembler is throwing following exception: Unhandled exception at 0x0110101a in IndirectoffsetAddress.exe: 0xC0000005: Access violation writing location 0x0110004d.

How should I overcome this problem?