NOT ABLE TO UPGRADE

[Istituto Beck]

I'm trying to upgrade but I allways receive the same error:

UPDATE `core_output_cache` SET `cache_expire`=0 WHERE `cache_expire` IS NULL;
ALTER TABLE `core_output_cache` DROP INDEX `cache_expire`, CHANGE COLUMN `cache_expire` `cache_expire` INT NOT NULL DEFAULT 0 COMMENT 'Unix timestamp of when the cache expires', ADD KEY `cache_expire` (`cache_expire`);

I did it but the error doesn't dissapear and I cannot go forward

Anny ideas?

Even upgradin mannualy doe'nt work because when I try to download the following message appears:

Problems during creation of Your download pachage

[Marc]

We would need to look further into this for you, however the access details on file appear to be incorrect or missing. Could you please update these details by visiting your client area, selecting the relevant purchase, then clicking "Review/Update Access Information" under the "Stored Access Information" section. 

We look forward to further assisting you.