On many systems your .signature (and .plan, .project, and .forward) needs 
to be world readable and your home directory needs to be world "executable"
(which means the world can go into that directory).  To check these
settings:

Type...          In order to...
-------          --------------
cd               Go to your home directory.

ls -l .filename  Check the permission: it should say -rw-r--r--
                 (Replace `.filename' with the appropriate file name.)

ls -ld .         Check permission of home dir: it should say drwx?-x?-x
                 The ?'s may be r's or hyphens or one of each (i.e.,
                 drwx--x--x, drwxr-xr-x, drwxr-x--x, drwx--xr-x are
                 each acceptable.)
If these aren't set correctly repeat the steps given in 1.1 above for
setting up your .signature.

If you are still having problems read the man pages for your newsreader,
news poster, or mailer and search for the string ``signature''.  There may 
be a variable you need to set in order for the ~/.signature to be appended.

Type...                 In order to...
-------                 --------------
man CommandName |less   Open man pages for CommandName (elm, pine, nn, tin
                        trn, Pnews, etc.) and pipe through less.  If your
                        system doesn't have less replace it with "more".

/signature              Search for first occurrence of "signature".

n                       Search for next occurrence of "signature".
                        Repeat the search until you find the appropriate
                        section of the manual.

u                       Page up half a screen. (This works in less but not in
                        more.)

[Space]                 Page down a screen. (This works in both less and more.)


For more information on reading manual pages see the man(1), less(1), and/or
more(1) man pages.