If the Validate and Process buttons are greyed out in the journal upload template then please try the following:
Close all excel sheets and reopen only the affected.
Templates can become corrupt over time and so it may be necessary to create a new one, and copy the data across.
Ensure the template being used is opened from your local PC drive and is saved to your local PC drive. If you are using a template saved to and opened from a shared drive, this can cause the template to be corrupt as this is being used by multiple people therefore the document is unsure where to point to obtain a connection.