Image Names

I am inserting a series of tiff images of standard details. I get the
message:

"The file you have chosen cannot be used as an image name"

I understand there can be various reasons for this (existing names,
unusable characters, length...).

But what are the precise naming rules?

The original file name is:

DE-ESC-3.1.2.1.001.tif

I now try to make it DE1211. It won't let me. I go with its ultimate
suggestion of DE-ESC-3.
If I reopen the image manager, I can rename it to DE1211 like I wanted to in
the first place.

I did post this in 2004 group...and got no answers. I figured there may be
more knowledge of internal acad naming rules here.

Terry S.

 

As best as I can remember you can't use a dot except just before the extension.
You also can't use "/" "\" "&" or "*" in the name.
When you rename the tiff don't forget to include the extension.