There are many errors at the HHTP process log files :
default:1 main Error: Can't open a socket on , port 80
default:1 main Error: Can't listen for HTTP on :80
default:1 main Error: Can't start server, exiting.
Can you try restarting the HTTP process : " SRX# run restart web-managemet"
Also can you try rebooting the SRX
If both didnot solve the issue , can you paste your configuration & indicate through which interface are you trying to access the SRX Jweb
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