Error after logging in during checkout

I am getting the following error after I login as a returning customer during checkout

Notice: Undefined index: grams in /home/xxxx/public_html/xxxx/administrator/components/com_hikashop/helpers/weight.php on line 59

Something to do with weights ?

In the "weight units" option of the configuration, remove the "grams" you added and add "g" instead. Then, you will have to change it for your products and shipping methods as this is not a valid weight unit.

Thanks - not sure why some products had grams instead g

But still getting an error.

---

Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request
...
More information about this error may be available in the server error log.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

---

I have checked the logs and it is saying File Not Found "/component/hikashop/checkout/step/step-1.html"

Any idess? Thanks

Will I try and reinstall Hikashop? If so will this delete any settings?

404 errors are usually coming from SEF. You should first try to turn off SEF in the joomla configuration.

Reinstalling HikaShop won't delete any settings.

I turned off SEF in Joomla and still an error. Reinstalled Hika - still no good. The logs are still showing the same error - missing page but now showing the non-SEF URL for step 1. There are 2 lines in the log - one is 406 error and the other is a 500 error?

On the first page of checkout, I have the hika components of Cart / Coupon / Terms and Conditions.

I notice when I click next that it doesn't matter if you check Terms and Conditions or not - it still moves or tries to move on to the next step. Is there someone that needs a setting to make the checkbox for Terms and Conditions compulsory?

Is there anything else you can suggest to fix the errors?
Thanks

I'm talking about the PHP error logs. The "file missing" error is not a PHP error from the PHP error log but an apache error from the apache access log.
You're not looking at the correct log.
You might want to ask your hosting company about where to find that log.

So you're talking about a 500 error ?
Try that modification then:
www.hikashop.com/forum/2-general-talk-ab...t.html?lang=en#48217

The Terms and Conditions is compulsory. It will tell you at the end of the checkout, if you're missing it. You should put it in the last step of the checkout, or change like that:
www.hikashop.com/forum/4-how-to/38499-ch...s.html?lang=en#38647

Thanks - the mod to the checkout address page didn't work - still get the error. Checking with my host to see if they can shed the light and also tell me where the logs are.

Have changed the T&Cs - thanks.

EDIT: Host came back saying this is the error: Premature end of script headers: index.php

I have googled and tried a few things but nothing. Would something in Hikashop cause this?

Mmm. That error doesn't give any info either... it just means that the page processing stopped in the middle...

Could you give a link to your website so that we can see that ?

I am not sure why but pestered my website host to look further and received a message that it should be fixed which it now seems to be. So a server side thing - not hikashop.
Thanks for your help