HTTP 404 error on Wordpress build only with certain browsers

I have posted about some sites I’m developing. Quick question. I am having issues seeing my site on certain browsers, specifically Firefox and Chrome on an Android OS.

I took a look at the access.log and this is what popped up:

67.212.188.154 0.089 - [11/Oct/2015:18:50:49 -0400] domain.com “GET /a HTTP/1.1” 404 11028 “-” “SiteLockSpider [en] (WinNT; I ;Nav)”

No problems on Mac or Windows browsers.

I followed other advisers who say to make sure the hostname is correct. Originally it was wrong.

My host settings:

ip xx.xx.xx.xx.xx. domain.com hostname

ipxx is my #, domain.com is the site, and hostname, my hostname.

No dice. Any suggestions? Is there a local server cache I need to purge here?