I am assuming this is IE. About:blank, if I recall, is not an error page so I am working in a vacuum. Because IE likes to give friendly errors and I have not worked with IE in a long while, I will take another approach. I have not had to do this for a while, so if I miss something, I apologize up front.
Check your log file to see if you are even accessing your site. If you are not, then try the following.
Do a nslookup of the domain name. You should get an IP address in the result. If you get an IP address, make sure that is the IP address that you expect and ping that IP address. I an not sure how or where your site is hosted. If it is on your own network then likely you need to create an entry in your hosts file to a private IP address to override any domain name lookup. Windows can get a bit weird and not resolve the name until the any TTL has expired so it could be a while before nslookup or a browser can see it. Even when the name resolves using nslokup, it can take the browser a while since these are using two different resolvers.
Find the Apache config file (possibly) /etc/apache2/apache2.conf. Look for the
I took a look at my confg to see if there is anything that could trip you up and I do not see anything that comes to mind. I would try another browser like Chrome since IE does funny things. I would ensure that you can resolve the domain name to a proper IP address, then ping to make sure you can reach it. If you need to, search for wget for windows in google and download a trusted copy. Wget is more technical, but it is a command line HTTP protocol app that can tell you more about what is going on. You can use Lynx too. Lynx is a command line browser. Both are somewhat raw and do not hide errors. But they may also be beyond your scope if you are very new to this.
Push comes to shove, try removing anything in the .htaccess file and changing the Options -Indexes to Options +Indexes to see if you can do a directory browsing of the site. Also make sure that you really do have an index.html file.
The idea is to make sure you are actually getting to the site and that your various config files (.htaccess is also a config file) are not standing in the way. Once that is done then you can reconfigure your site as needed. Sometimes stripping the process down to the most simplistic form can really help narrow down what is going wrong.
Sorry that I am no longer IE savvy. I found that it got in the way of valid development efforts and stopped using it.