Fayun Luo wrote:

I have koha 1.2.3 installed recently. Now I want to update to 1.9.3. What is the easiest way to do it?

If update is not possible, somebody tell me how to uninstall the koha 1.2.3 version.

for instance, no upgrade tool is provided. It should be done in 4 separate parts : * upgrade database * import MARC21/UNIMARC parameters and modify them to fit your needs. * run a script to move biblios from kohaDB to marcDB I've asked katipo to see if they were willing to do such a tool, as they are the best 1.2.x users. -- Paul POULAIN Consultant indépendant en logiciels libres responsable francophone de koha (SIGB libre http://www.koha-fr.org)