Checkout failing to process through. server 500 type errors

Your version of Zen Cart® appears to be current.
(You are presently using: v1.5.1)

ZenExperts,

I've sent this email to IPower and didn't get any help as expected from what I read. It seems something suddenly corrupted or has been hacked. I don't want to lose what we have for customers and orders in our database.

What do you guys see when you try this?
What would be your suggestion to try and fix this without corrupting the database and product work we have done?

FYI - On the site many pictures are missing. that is normal. we have not added them all yet.

http://www.tredwayspeedshop.com/TredwayStore

We are having a problem with the PHP server crashing when users checkout items at our store as of recently. Is there something limiting our PHP or MySQL query or calculations? We have not changed our admin setting on our end. Our E-site has been down the last couple days. Our last resort is contacting iPower. If you could just add a few items in our cart and try to checkout and you'll get the server 500 error.

thanks, rob Jackson

Any suggestions to repair this without data loss is appreciated!

Unfortunately, this type of error can only be defined by your host as they have access to the server logs

https://www.zen-cart.com/content.php?105-why-am-i-getting-500-internal-server-error

Backup your database daily to prevent losing your up to date data

Use phpmy admin

https://www.zen-cart.com/content.php?144-how-can-i-do-a-site-backup-or-use-phpmyadmin-for-database-backup

Do you have any myDEBUG*.log files in your store's /logs folder?

oleancomputers:

Your version of Zen Cart® appears to be current.
(You are presently using: v1.5.1)Your post is dated March 4, 2016 ... but the proper latest version of Zen Cart as of this date is actually v1.5.4 ... not v1.5.1 as yours says.
This might suggest some files are damaged on your server, perhaps due to mixing versions of files when installing plugins etc.
It would be good to at least go to Admin->Tools->Server Info to look at the actual ZC / Database versions and version history and post that information here for review.