If this is a warning message, it may be hoax software. I have seen this before, but I am sorry that I don't remember how to fix it. However, you might search internet for the specific message and you can rid of it. Don't respond to the message though.
The files are probably saved to a virtual image of the SD card. In order to actually get them written to the card, you would have to tell the operating system to unmount, eject or otherwise remove the SD card before physically removing it. Usually a restart or shutdown will do the same thing. The operating system will then write the image to the SD card, and if it is not doing a restart or shutdown, may tell you it is safe to remove the card.
This is done to increase the lifetime of the card. Every time you write to it, it wears out a little. Consequently, the system waits until you are done working with the file before doing the writing so it doesn't waste writes on stuff that will be edited right away.
To highlight text permanently, similar to a highlighter on paper, use WordPad instead of Notepad. Find WordPad by searching on the Start menu or Windows 8 Start screen. In WordPad, first select the text you want to highlight, and then open the drop-down menu next to the highlighter icon, located near the font settings. Pick a color to highlight the text. After setting the color, merely click the highlighter icon to highlight selected text with the same color. Word 2007, 2010 and 2013 offer an identical feature, used in the same manner. Word also includes the option to click the highlighter icon first and then select text to highlight How Do Highlight Text in Notepad eHow
Click and drag on text in Notepad to select it. To quickly select a single word, double-click the word.
If you prefer to use the keyboard, hold the Shift key and use the arrow keys to select text in any direction. Hold Ctrl and Shift while pressing the left or right arrow key to select one word at a time instead of a space at a time. To select the entire document, press Ctrl-A.
After selecting text, pick a function from the Edit menu, such as Copy.
First, tap on your Settings app (or icon if you have a shortcut on one of your home screens). It's the one that looks like a cog or gear. This will bring up the Settings menu.
On your Settings menu, tap on Wireless and network.
You should now see a list of wireless-related menus. Tap on the Flight mode - also generally known as Airplane mode - to disable all wireless connections. You'll know it's working because you get an airplane icon on your notifications bar.
Great, now you won't be getting any incoming calls. But wait! Now your Wi-Fi connection isn't working, either. Nice going, Jason, you regular Einstein. Hold on your horses, though, because we're not done yet. On that same wireless submenu, tap on Wi-Fi settings.
Click the option to Turn on Wi-Fi.
Look at your notification bar on your home screen again. You'll still have the airplane icon on, indicating that you won't get any calls. But you will also start seeing a Wi-Fi signal icon. Voila! Now you can connect to a Wi-Fi enabled router or hot spot without worrying about getting roaming charges.