I've just downloaded GVIM for the PC and MacVIM for the Mac and they both have different behaviour to the VIM I was using in MSYS.

Here's the problem. I bring up a file in VIM and enter insert mode. I can no longer delete any of old text. I can insert new text and delete them just fine so I know my backspace and delete keys are working. What's even more annoying that if I move the cursor to another line and come back to my original one, the new text I've typed becomes undeletable as well.

The command line VIM allows me to delete old text in insert mode but the GUI versions do not. I've looked in the options and googled but have not come up with anything.

Does anyone know how I can make the GUI version behave like the command line version of VIM?