Not able to change the extension of a file

[Sandy22]

I don't know why, but this is a very weird issue which I am facing. I actually don't know if it is any real problem or any bug in my computer. I am using Windows 7 Ultimate x64. The issue is that I cannot change extension of a file. I tried to change the extension of a file from .txt to .rtf
But was not able to do. Got an warning message saying "If you change the a file name extension, the file might become unusable."
So will it really create any problem. Any solutions please.

[Lillebror]

Hey don't worry it's just a safety warning. It will not affect the file at all. You can also try this method. Open the text file in notepad as you normally do with an txt file and then click on file and then on Save As and then select to save as rtf file format and should work for you. I mean this is not at all reisky and no need to worry if there will be any problem with the file in later future.
So try it out.

[Sandy22]

Well that's right, but there is this problem I don't get any "YES" or "NO" button on the warning message. I don't know why but I do see there is place for "YES" and "NO" option but there are no buttons present over there, it looks like there is some bug in this. But yes when I try to change the extension from any file placed on desktop then I do get the same warning message but I also get "YES" and "NO" buttons. And everything looks fine at desktop.
What exactly is this.?

[Dr. V]

Well now as you said that you don't see any buttons over there so, traditionally you can try to hit enter which always works. This is a bug which was then fixed in the later version. I guess you are using the Beta version of Windows 7 which is why all this weird things are happening with your system. Well and as explained before if you really want to change the extension then open it and change it when you will be saving it.

[MrChris-]

Even I had this same issue before. I was trying to change the extension of user32.dll to user32.dll.bak. And even I didn't get any option buttons over there. Actually my computer froze at that screen and there was nothing which I could do. Not even task manage could see it. SO in order to get rid of it I had to restart my system.
And not only this bug but there are many different software incompatiblity with this beta release.