S7 1200 WEBSERVER

Hi there!

i'm new in the forum. I start to work with S7 1200 CPU1214AC/DC/RLY firmware 4.4 i create my HTLM pages and download in to PLC. Everything work well i can read dat from DB or tags but if i try to write from my HTML dose't work. I find on line a tutorial from SIEMES i copy a couple of examples but dosen't work  i use a password but nothing. If i modify the variable from the SIEMENS page gave me when i type the IP i can change the variable.

Please some one can help me because i diden't know what my problem is 

Thank you soo much 

Sergio