@mc2grande - I just had a quick look at IONOS and I couldn’t find any details about exactly “what” their hosting solution provides beyond broad marketing terms. Please ensure they are providing the standard Apache+PHP+MySQL(MariaDB) ChurchCRM relies on (we will be dropping support for PHP 7.0 soon). We have a number of PHP modules ChurchCRM relies on documented here https://github.com/ChurchCRM/CRM/wiki/Installation#php
Without any error messages, or logs there’s not a lot I can suggest at this stage. Please try to get hold of the web server error and access logs (ie, Apache error/access) as these often reveal problems you can’t see in a browser.
@VanBawiThang - there are two errors in your log sample that seem to be relevant. One is saying a pledge amount of of 1 million (1000000) is out of range. Try using a lower amount and see if that changes anything.
Secondly, this error may be temporary, but the unless you have removed the database name and username, it was never going to succeed either:
[2019-12-04 10:09:32] defaultLogger.ERROR: ERROR connecting to database at ' ' on port '3306' as user '' - MySQL Error: 'Host 'ip-43-255-154-43.ip.secureserver.net' is not allowed to connect to this MySQL server'  
I’m going to double check the DB schema and make sure there aren’t any limits on table values etc.
@VanBawiThang - the
pledge_plg table has a limit of 8 digits with a precision of 2. This would limit pledge amounts to a maximum of 999,999.99. When. You nominated a pledge amount of 1,000,000 it is actually trying to be stored as 1000000.00 which is 9 digits. To work around this, you could nominated an in-range pledge or alter the schema to support more digits in the
If local currency requires storing such large numbers, please file a ticket so we can adjust the schema for everyone :)
@VanBawiThang - the following SQL should fix the problem with out of range pledge amounts:
ALTER TABLE pledge_plg MODIFY COLUMN plg_amount decimal(9,2)
That will allow amount up to 9,999,999.99. If you need 10-99 million, change the
@mc2grande - the 3.5.5 release is fine. The problem sounds very much like permissions on your web server. Please ensure the permissions are set correctly: https://github.com/ChurchCRM/CRM/wiki/FAQs#internal-server-error-500
Even though you’re not getting 500 errors, the link above has the permissions you need to set. Unfortunately ZIP files don’t carry permission information and consequently are often not correct after unpacking on your web host.