Hello, it says battery in wireless mouse MK300 is dying, and needs replacement. But I don't know how to take out the battery. Can you help me? Thanks. Jun

Ok don't worry. Sounds like you need to Unplug the mouse for a sec then re-plug it back in to reset it. If the mouse is wireless then try replacing the batteries. Cause a wireless mouse can still turn on if batteries are weak but won't have enough power to connect to the receiver connect to the desktop/laptop. Try doing so and let me know if this solves your issue.

Link to instructions

Looks like you press down and pull back on the bottom half of the top cover as outlined in the picture.

For the keyboard, move the cover with a battery sign on the bottom of the keyboard to the side and you will see the battery. For the mouse, press down the rear half of the top cover of the mouse and move it backwards. The steps are on the manual about troubleshooting batteries.
http://www.logitech.com/repository/1408/pdf/24495.1.0.pdf

Q: Changing the batteries in my MK300 How do I change the batteries in my MK300?
Wireless Desktop MK300
Model Number:
Y-R0002 (Keyboard)
M-R0006 (Mouse)
Battery Requirements:
Keyboard:

• Requires 2 AAA alkaline batteries.
• Expected battery life is up to 15 months.

Mouse:

• Requires 2 AA alkaline batteries.
• Expected battery life is up to 8 months.

Installing New Batteries
Install the batteries for your mouse and keyboard by making sure the batteries face the correct direction as shown in the image below.

Battery Replacement Tips

• For best battery performance, always use quality alkaline batteries.
• When replacing batteries, make sure the replacement batteries are new and are within the manufacturer's expiration date.
• Do not mix old and new batteries.
• Do not mix batteries of different brands.
• Do not use rechargeable batteries in this product.

underneath the mouse should be a clip/snapon port or a port shut with a screw. open it and thats where the battery goes.

follow the instruction on this picture and open your mouse.
Position the mouse as you would normally use it and slid the top down as shown in the picture attached here.

You can get a new one from the nearby logitech shop or from the place where you bought it

Thanks

The top part of the mouse slides out. It is the section where the name logitech is written. Check the picture to view the mouse with open compartment.

There's a couple of things you can check:
1. Check that there are good batteries in the mouse.
2. Check that the connection on the receiver to the computer is good. Re-seat it (unplug it and plug it back in) to be sure.
3. check the synchronization of the mouse to the receiver. Push the button on the bottom of the mouse and the button on the receiver and see if that helps.

If not, then shut the machine down, and start it up without the mouse receiver attached, then plug it in when the login screen or "welcome" screen comes up. it might take a minute or two to sense that it's there, but that should be the final test. I have not had a single broken logitech mouse, and have usually given them to a friend when I upgraded to a newer, better one. If the steps I outlines don't work, then think about replacing it. THere are decent sets now including the MK300 series which I'm typing on now that are economical and have decent range and functions.

This is either a problem with your wireless mouse usb detector, or simply the battery.

In most wireless mice, there should be screws at the bottom wher you can unscrew and replace the 2 small, circular batteries.

For the usb wireless detector, check it for any scratches and dents. If there are any, you will have to buy a new mouse.

Hope this helps and please rate!