When you move you move into a Google Spreadsheet cell you find that the data in that cell gets erased, and the spreadsheet automatically saves it. You are also not able to undo it, because that doesn't work too! I was facing this problem for quite some time. Googling didn't help. Finally I found a solution on my own.
Problem Switching between Windows
This problem was probably related to another problem that I was facing on my windows machine. About since two years back I was not able to switch between windows on my PC, but I had found a workaround for this - minimize all the windows, hold the control key down, and then click on the window you wanted to switch to. And, because of that workaround, I never bothered to go researching about this. I did try to google for things in this regard but nothing worked for me, and neither were any solutions very accurate ones. So I had almost become used to my PC, and adapted to working that way.
Computer Beeping Continuously on Startup
In addition to the above issue, my computer gave a long beep at startup, but after a small wait it could come back running. This problem also persisted with the above problem - the problem of switching the windows. Again, it never halted my work, so I overlooked it and had learnt to live with it. So my computer was behaving in a strange way all trhough these days. When I googled about this problem, the suggestion that came was regarding some fault in the battery. This one looked plausible because my Sony vaio laptop was already 4 years old, and its battery was never replaced in between. It was surely an old and worn out battery. I decided not to change the battery, and keep using it till it really stops one day.
Google Spreadsheet - Loss of Data
But one day... I lost a precious phone number from my google spreadsheet when the cursor moved into that cell erasing the phone number. That phone was very urgently needed, and it was gone, without any chances of future recovery. That was not the only loss that occured. Wherever the cursor sunk, it kept on erasing every single alphabet it found!
That was a wake up call.
As usual, I googled up again. Some people suggested uninstalling the graphics driver. I did that, but nothing worked. Then the response from the Google team was that it is a hardware problem. This one looked promising. Then another response was that there was some nasty application that was sending un-wanted keystrokes that was causing the problem. At this my brain went stitching these ideas together into one - YES ! It's the Sony Keyboard. Long time back, I had spilled coffee on my laptop, and the keyboard had started giving problems. At that time, I had attached another keyboard(the USB desktop type keyboard), and solved the problem that way. But as I went back in time to that day, I became 100% sure that the laptop had started beeping since that very day, like it beeps when a key is stuck. The problem of switching between the windows was also related to the Sony Keyboard continuously sending keystrokes.
All the three problems now converged into in single endpoint - the Sony Keyboard.
Problem Solved
It was a sunday, and I decided to rip open the laptop to disconnect the keyboard. For this I youtubed to a video that showed that the Sony Keyboard can be torn out from the front only. I was ready to take the risk because it was already faulty. I was too fast in tearing it - I was almost mad at solving the problem - so without bothering about damaging the laptop, I got the keyboard out, disconnected the "bus" cable, and used a cello tape to fasten the irreversibly damaged keyboard. Then I restarted the PC. It didn't beep for the first time in two years. Then I tested by opening two windows - I was able to easily switch between them ! Then I shut it down. Waited for 5 minutes, started it again, and everything worked fine. "It's electronics, it will now work always.", I told myself. Then I tested the Google Spreadsheet - yes, nothing was deleted by the cursor. I found one more thing that my PC has become faster and more responsive.
Then I decided to write this article so that people like you may be helped.