When you edit HTML templates manually Help+Manual does not verify the code in any way. You are entirely responsible for checking and testing the code you write. It is a always good idea to back up your template in an external text file before editing.
Nowadays you will almost always choose an HTML skin to publish your project to WebHelp or HTML Help/CHM. A skin is a special kind of Help+Manual project without topics that only stores your HTML templates and all the settings relevant for HTML output to these two formats. When you choose a skin, the templates and settings in the skin completely replace those in your project.
Normally, a skin is pre-designed and you don't need to change anything. However, if you do want to change something, you must do all your editing in the .hmskin skin file. Editing in your Help+Manual project won't have any effect because those templates and settings are not used.
To edit a skin, make a copy of the .hmskin skin file in your project folder and then open it in Help+Manual by selecting .hmskin as the file type to open in the Open dialog. All the templates and settings are in the same places as in a normal Help+Manual project.
Exception: HTML Export Options
The HTML Export Options section is not stored in skins and needs to be edited in your project.
You can always revert to the standard default template with the Reset Defaults button (see below), but you should make backups of working versions of your own edited templates before you make more changes. Reverting to the default template overwrites the entire template with the standard version – it does not return you to your own previous version.
Copy the entire contents of the template, paste it to an editor and save it in an external file. Then if anything goes wrong you can always paste the original version from the saved file back into the template editing window.
Sooner or later, editing your HTML templates will cause errors in your output. This cannot be avoided and it happens to the best of us.
If you make a lot of different changes before testing your output it can be very difficult to localize which change is causing the problem. To avoid this kind of frustration you should always make changes gradually, one step at a time. After each change, publish and test your output before proceeding to the next change. Then you will always know which change is causing the problem and it will be much easier to correct.
In WebHelp you can also edit your output files directly to avoid the publishing step. However, doing this can be a little tricky because you always need to remember to copy every change back into your project before proceeding.
You can always restore the default template. Just select Reset in the template editing screen.
However, this will completely replace your version of the template with the standard version, so you will also lose any earlier changes you may have made to it. If you have not already done so, make a backup of your own version before reverting to the default