Help me about the toolbox ?

Help me about this problem. My symbolic toolbox still exist. but I can use it. for example the syms command. Why ? I don't have this error before :(

[Geoff Hayes]

Nguyen - the links in your question are invalid. Please copy the error message from the MATLAB Command Window and paste it into your question.

[Nguyen Trong Nhan]

Yes. I edited

[Geoff Hayes]

In the Command Window, type

 *ver*

to see if which versions of MATLAB and the toolboxes that you have.

Then type,

 which syms -all

to see the location of the syms funciton/file (if it should exist).

What is returned for both?

[Nguyen Trong Nhan]

ok. I see. thanks

[Image Analyst]

You see what ? Was it listed or not? Did you have a temporary/trial version that expired?