Can't draw an angled line - Why?

I have several drawings (AC2K) created by someone else that won't allow me to draw a line at any angle other than horizontal or
vertical. It also won't allow me to dimension at an angle.
I know very little about Autocad - can someone tell me what is causing this?
FWIW, if I create a new drawing, both drawing and dimensioning work "normally".
Thanks.
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F1 ... Look up ORTHO mode. ___

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OK - Thanks.
wrote:

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Try pressing F8 to switch ORTHO 'on' and 'off'.
snipped-for-privacy@comcast.net (Martin) wrote:

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