Hi,
Can you give us your last log files in your projeqtor/files/logs, you probably have the reason of your issue on here.
Once we got it, we can see what we can do for you.

Hi Damian, Thanks for the reply
Here is the log.
It seems to be related to the version of PHP installed on the server.
We downgraded to v12.2.3 and it's ok now.

Thanks,

Hi,
It seems your php version is too old for running on this projeqtor version, you can check Technical information & prerequisites on https://www.projeqtor.com/en/help/ to know the minimum compatible version you need.
If your upgrade your php version in your server that would fix some issues.
However you got another issue, you need to give your php user (www-data on Linux) on server write rights on projeqtor directory, so that projeqtor can create directory and write files for cache management.

Hi,

I am having the same issue (white page after upgrade), however, if I downgrade, and then re-upgrade, I get a "35 ERRORS DURING UPGRADE TO 13.0.0" message - advising me to check the error log. However, there is no error log in the /files/logs folder, so I can't see what the problem is.  I am upgrading from 12.5.4 to 13.0.0, and I am using PHP 8.4.

Any advice on what to do next would be greatly appreciated.

Normal : if you revert Code wirhout restoring Database, the updates in DB are preserved.
So when you try to migrate again to next version, updates fail because changes were already done (creation of tables, columns, lines, ...)

Thank you for the update. I did wonder - as I hadn't received any errors during the initial upgrade.

Is there a guide (or advice) available for troubleshooting the 'white screen' issue? Ugrades to Projeqtor new versions have never caused any issues before.

Thanks again for the help.