Upgrading Drupal

I've searched, but found nothing relevant. Hence I would be graceful, if there would be a generally written documentation on:

"How to downgrade a Drupal module? Considerations & limitations."

Aspects, which should be answered by this documentation:

Hello friends,
recently i have upgraded the drupal website v5.10 to 6.19. Before upgrading, i have disabled all the modules. after upgrading i have enabled all the modules together(some web pages had information that we should enable the CCK . later all the required module.) Now if i go to admin ->Content management->content type ->edit article(or any other like forum,blog) i can see only to edit the template...ie Display field, Manage field is not visible. Since it is most important to my website creation, i am struck in this problem.....

Hi,

I am having a huge issue with one of my client's site. I backed-up my database and using plugin manager updated a few modules including backup and migrate, webform, notifications, imageapi and possibly one or two others. Before even getting to run update.php on tha database I got an error. The database was locked and nothing was working - the site is brought down.

I have rolled back to several old databases, going back even a few days of development. I have disabled the modules and more listed above but the database still locks and is not released. I have contacted my hosting company and they say it is the following UPDATE query not releasing the lock.

UPDATE drupal_variable SET value = 'i:0;' WHERE name = 'dev_query'

• I have looked at the Drupal variable table and have found there to be no dev_query field.
• I have looked online and seen dev_query to be mentioned in the same context as the devel module*.
• I have search for the variable dev_query in the modules folder and have not seen an UPDATE query like the above or dev_query being loaded with the value 'i:0;' using variable_set(), I can only see variable_set('dev_query', 0); in devel.install

This was an area I thought I was not a newbie in anymore. I have upgraded many modules for a year now and now something new!

I have many modules which need updating and when I upload them as I always have to sites/all/modules the files don't extract properly.
eg:

image-6.x-1.0.tar (2).gz
File Type: image-6.x-1.0.tar (2).gz: POSIX tar archive

SCALAR(0x1708570)gzip: image-6.x-1.0.tar (2).gz: not in gzip format
SCALAR(0x1708570)

what's wrong? Please help thanks.

i trying to migrate content drupal5 to drupal6.

but still having problem.

give me proper solution with steps.

in our project we need upgrading right now(migrate drupal5 to drupal6).

but....

mojor issue is that,i cant migrate my old data into drupal6.

please give me proper solution.