i wrote a website for someone and want to disable it after two mothns.  

(because he should pay for it after two months, if not i should blow it up)  

so, i called a DateTime WebService from my web site for getting DateTime.Now!  

i should keep web site start time some where in his server and i want to write a text file in C:\Windows\System32.  

but when i tried to write a text file in this path, i got the error below : 

```
Access to the path 'C:\Windows\System32\ is denied.

```

at this time i have remote access to his server and can change permissions.  

but if he change his server, he will see that error and can find that file and edit it easily.  

would you please learn me a way for fix that error or another way for saving web site start time!(mean where?)  

database is not a good idea, because he has access to his database.  

i can write that file on c drive and change it's attributes (hidden and system), but he can find this file easily. 

would be appreciate for some help