Can you reach website cmarkn.com through Comcast network? I can't.

I can reach the site. When one customer cannot reach a site but others can, it usually means the site is blocking that customer's public Comcast IP. You can look up your IP at https://www.google.com/search?q=IP. You'll probably need to ask the site's admins for help with this.

My trace looks like:

C>tracert -4 cmarkn.com

Tracing route to cmarkn.com [69.89.31.233] over a maximum of 30 hops:

1  11 ms   2 ms   2 ms router1 [192.168.1.1]
2 14 ms 12 ms 12 ms 96.120.9.181
3 14 ms 12 ms 12 ms te-0-6-0-0-sur02.york.pa.pitt.comcast.net [162.151.68.57]
4 12 ms 12 ms 12 ms 96.110.24.214
5 13 ms 13 ms 13 ms 96.110.25.65
6 19 ms 19 ms 19 ms be-34-ar01.mckeesport.pa.pitt.comcast.net [69.139.168.141]
7 28 ms 28 ms 28 ms be-7016-cr02.ashburn.va.ibone.comcast.net [68.86.91.25]
8 27 ms 28 ms 27 ms be-1402-cs04.ashburn.va.ibone.comcast.net [96.110.32.181]
9 28 ms 28 ms 27 ms be-1412-cr12.ashburn.va.ibone.comcast.net [96.110.32.214]
10 45 ms 44 ms 43 ms be-302-cr14.350ecermak.il.ibone.comcast.net [96.110.32.102]
11 45 ms 44 ms 44 ms be-1414-cs04.350ecermak.il.ibone.comcast.net [96.110.35.61]
12 44 ms     *      44 ms be-1402-cr02.350ecermak.il.ibone.comcast.net [96.110.36.110]
13 65 ms 67 ms 65 ms be-10521-cr02.1601milehigh.co.ibone.comcast.net [68.86.85.170]
14 67 ms 64 ms 68 ms be-12021-cr01.champa.co.ibone.comcast.net [68.86.84.225]
15    *         77 ms 78 ms be-7922-ar01.saltlakecity.ut.utah.comcast.net [68.86.90.226]
16 80 ms 78 ms 79 ms po-1-rur01.orem.ut.utah.comcast.net [162.151.9.186]
17 77 ms      *        77 ms be-11-sur03.orem.ut.utah.comcast.net [162.151.9.190]
18 80 ms 78 ms 83 ms 50.225.56.182
19 78 ms 79 ms     *        eth3-33-3.prvspn001.net.unifiedlayer.com [162.144.240.143]
20 78 ms 79 ms 78 ms po97.prv-leaf6a.net.unifiedlayer.com [162.144.240.11]
21 82 ms     *        89 ms box433.bluehost.com [69.89.31.233]

Trace complete.