Yes, it has something related to the syntax, but I am searching for a method to perform the following:

UPDATE modules
SET ServerID = boards.ServerID
FROM boards,modules
WHERE modules.ID = boards.ID

this does not work. I am using MySQL

Do this:

UPDATE boards,modules
SET modules.ServerID = boards.ServerID
WHERE modules.ID = boards.ID

Read MYSQL UPDATE syntax at

You may also perform UPDATE procedures covering multiple tables ....

UPDATE items,month SET items.price=month.price

The preceding example shows an inner join that utilizes the comma operator, but multiple-table UPDATE claims may use any kind of join allowed in Choose claims, for example LEFT JOIN.

UPDATE modules
SET ServerID = (SELECT b.ServerID FROM boards b WHERE b.ID = modules.ID)
UPDATE modules
ON modules.ID = boards.ID
SET modules.ServerID = boards.ServerID

UPDATE syntax doesn't include FROM

FROM is intended for Choose.

if you wish to mix the 2:

UPDATE modules SET ServerID = (SELECT boards.ServerID FROM boards WHERE boards.ID = modules.ID)