Dimension tick marks disappering (pos7i7)

For some reason the tick marks on my dimensions are invisible, no matter what I set the size to. When I'm drawing the dimension, I see the tick marks flash for a second, but as soon as I complete the command they are gone. If I change the "arrow type" to arrows, I get a blank space at the end of the dimension line instead of the arrow. I tried importing a dimstyle from another drawing where it had worked perfectly, and when I used it in the new drawing, same story, invisible tick marks. Is there some setting I'm unaware of that controls this? Any advice would be appreciated.
pos7i7

pos7i7 wrote:
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The arrowheads/tick marks are simply blocks. Is it possible that they've been redefined to something terribly inappropriate?
Try inserting one using INSERT and see what appears.

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Is layer 0 of or frozen?
Generally when something like happens it is realted to some problem with the block that is used for that dimension style ending by AutoCAD. As the block is already in the drawing, any new dims will just use this block rather than redefining it.
Try exploding the dims & see if the end appears, & if you can refedit it. Try wblocking all the dimsout to a different file, purge your drawing & insert a new dim from scratch with the same style name, before bring back the old dims.
Matthew

Matthew Taylor wrote: <SNIPPED>
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FWIW:
INSERT TickBlockName will accomplish the same thing much quicker. ;)

On 21 Aug 2003 20:44:24 -0700, snipped-for-privacy@yahoo.com (pos7i7) wrote:
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Try changing the on-screen background colour and see it it makes a difference.
John B
johnbogie btinternet.com Put the "at" in the gap.

Thank you VERY much to everyone who commented on my disappearing tickmark problem. I didn't understand tickmarks were blocks. I discovered that my tickmark block had somehow been changed to a layer I had been trying unsuccessfully to purge . . . was able to refedit it back to layer 0, and voila! Everything was transformed. Never would have figured it out on my own. Thanks so much everyone for sharing your expertise!