The temporary tables exist with the 'nice' name only for the current session. Make sure you're not closing your connection, and use the same as you used to create the temporary table.

If you must use a different session and the other session's not closed, you might be able to access it by looking at the tables in ?tempdb?. They should have *long* names with your session ID in the name. If you pass your session ID to your other connection, you may be able to find the temporary table. But I don't know if your other session will be able to read from it.

...roboticus

Update: I should've mentioned that I've not touched a Sybase database in five years, so my recollections may be (a) out of date, (b) totally wrong, or (c) some combination of a & b.