Reading this thread, really highlights some critical mistakes or silly errors some e-Sword users make. Now, before going into some critical reminders of dos and don'ts, you can add me into doing some silly things which caused me a great deal of angst as a result of loss of data.
OK, first and foremost, and this is really important, and I can't stress this enough, never, and I mean, never ever use e-Sword's default study.notx (and for that matter, any of the other editors default filenames) to place your data in. Get into the habit of creating a new file and give it it's own unique file name. This way, you have a study notes that you can really keep a track of. Doing it all in the default e-Sword generated file can only be best described as a disaster on the way to happen. If you lose data by making some mistake, and irrespective that some have the blind faith that it can't happen, your file gets corrupted, then you will have no way of restoring that data.
To create a new study, topic, or journal file name you simply do the following:
- Press the Ctrl key and (using the right button) click on the blank (part of the) page on your editor. {For those who are left handed and have changed your mouse button settings its, using the Ctrl button and left button of your mouse}
- A context menu will pop up, and then click on New... in the menu.
- The New File Dialog window will appear.
- On the bottom of the New File Dialog, is a File Name ComboBox. Type in the filename for the new Study (or topic, or Journal note), in it, and then click on the Save button.
The next most critical thing you really have to get into the habit of doing (and if you don't, then you need a base ball bat fairly planted in between your eyeballs 
), is to regularly backup your file. This totally avoids a total loss of your data as you have a copy of your study files. Your backups are your lifesavers. Just about all Word Processors and other office applications will automatically do incremental backups of your data, and places it in a separate folder on your hardrive. e-Sword doesn't do that! You have to!
The best practice for doing a backup is relatively simple. Copy the file on a removable media, i.e., an external hardrive that plugs into a USB port, or a reasonably decent sized thumb, pen, stick, or whatever name you give it drive. For these pen drives and reasonably good size is about 8 or 16 Gigabytes. I use a 32 GB. An External portable hardrives sizes usually range from 500 GB to about a Terabyte (1000GB). Pen Drives are the less most option to go for. CD/DVD disks are another option you can use for backing up data.
The reason I backup on an external media, is because of the use the Hardrive and/or a solid state drive gets files (including software) can get and will get corrupted simply due to wear and tear.
Blessings,
