When I select line, the cursor is very jerky, like it is trying to lock onto a grid point . Any suggestions on how to stop this. I have just reloaded Autocad 2100 onto a new computer and as far as I know all the settings are the same. Apreceiate any help. 

Hello Phil, one clic on F9 ( snapmode OFF ) should be enough.

It goes with the GRIDMODE ON/OFF ( F7 ).You will have an idea of how it works if you set snapmode and gridmode ON, zoom very close to the grid and try to draw a line for example.Then you set snapmode and gridmode OFF.
philippe JOSEPH2018-11-15 07:22:05

Hi Philippe, Thanks for your help. I had already turned off grid and slaps, but I think I have now solved the problem. I went into Dynamic Input settings and unchecked "Enable dimension input where possible" this seems to have solved the problem. Cheers Phill.