It sounds like the issue with the pictures being corrupted is happening during the upload process. This could be due to a number of reasons, including incorrect file permissions, insufficient server resources, or a problem with the upload process itself.
Here are a few steps you can take to try and resolve this issue:
Check your server resources: Ensure that your server has enough resources (e.g. disk space, memory, CPU) to handle the upload of large files.
Check file permissions: Make sure that the file permissions for your wp-content/uploads directory are set correctly, allowing WordPress to write to the directory. You can set the permissions to 755 or 777 depending on your server configuration.
Use a different upload method: Try uploading the photos using a different method, such as FTP, to see if the issue persists.
Deactivate plugins: If you have any plugins installed, try deactivating them one-by-one and uploading a photo each time to see if any of them are causing the issue.
Check image compression: Make sure that the images are not being compressed during the upload process, which could cause them to become corrupted.
If these steps don’t resolve the issue, you may want to reach out to your hosting provider for further assistance, as the issue could be related to your server configuration.