If the site was in a subfolder, check ps_shop_url and make sure physical_url is "/" (without quotes) and the domain/domain_ssl are correct (the same domain has to appear in the ps_configurarion table, search for the PS_SHOP_DOMAIN and PS_SHOP_DOMAIN_SSl keys).
Also remove the var/cache/ (relative to PS_ROOT) content.
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If the site was in a subfolder, check ps_shop_url and make sure physical_url is "/" (without quotes) and the domain/domain_ssl are correct (the same domain has to appeat in the ps_configurarion table, search for the PS_SHOP_DOMAIN and PS_SHOP_DOMAIN_SSl keys).
Also remove the var/cache/ (relative to PS_ROOT) content.