Apache Won't Start

[OldHonky]

I am using Windows 7 Home Premium (x64) with 8Gb memory and 218 Gb free on my C drive.

Although I have been using XAMPP for several years (without wordpress), my coding knowledge is limited so please don't assume a good level of technical understanding.

I have recently downloaded and installed XAMPP version 7.1.1-0 and wordpress 4.7.2-en_GB which I have configured as multi site.

I followed on-line instructions at WPMUDEV. This worked OK and both XAMPP and Wordpress seemed to be functioning properly, but when I added new sites in Wordpress they were not there when I clicked the link. I just got a message saying that they were unavailable.

So I looked on line and it appeared that I had to enable mod_rewrite. I followed instructions to edit Apache/conf/httpd.conf, (I used notepad ++), and Apache wouldn't start. So I changed the settings back to how it was before and Apache still won't open.

Since then I have downloaded and installed Microsoft Visual C ++ 2015 Redistributable (86)- 14.0.23026, but that hasn't made any difference.

What is the best way to solve this? I thought of reinstalling XAMPP but I would like to keep the multisite wordpress.

In htdocs I have two folders :
"WP" contains the multi site wordpress folder with only one working site so far.

"Non WP" contains some hand coded sites that are in various states of development.

If I copy and back up these two folders, then delete XAMPP and reinstall it. Can I then just copy these folders back into the new htdocs and will it work OK? WPMUDEV's tutorial tells me to export the data base, but I can't open localhost so I can't do that.

Is there another way to fix this without reinstalling?

I would appreciate any help.

[Nobbie]

Can I then just copy these folders back into the new htdocs and will it work OK?

No, it will not work, you are missing all data.

WPMUDEV's tutorial tells me to export the data base, but I can't open localhost so I can't do that.

Thats correct, you have to export/import all data. Maybe there is an option in WordPress for export/import, otherwise you might use phpmyadmin. Last not least (if you do not change the MySQL release), it is sufficient to keep the "data" folder of MySQL (c:/xampp/mysql/data), i.e. make a backup of that folder and later, after installing a new Xampp, restore that folder to exactly the same path (you have to rename the new data folder to data.somewhat or so before, then restore the old data folder).

Is there another way to fix this without reinstalling?

Of course, you have to find out what you are doing wrong and why Apache fails to start. There must be a reason for it.