I'm sorry to hear that. It was working before I upgraded. Oh well.
Trouble is it seems a response to a ticket by a user wasn't being addressed by the system either. Before this upgrade I had a task in windows scheduled to run a batch file every five minutes. The batch used to contain the following line:
"c:\program Files (x86)"\PHP\v5.3\php-win -f c:\inetpub\wwwroot\osticket\api\cron.php
after upgrading to the 64-bit version of 7.3 that old batch obviously wouldn't work so I edited to batch and changed it to:
"c:\program Files"\PHP\v7.3\php-win -f c:\inetpub\wwwroot\osticket\api\cron.php
but then task scheduler started producing errors. First I got 0x1 which could mean permission issues and could mean it couldn't find the file. I checked the box in properties for the task to run with highest privileges. Then I started getting the error 0x80070001. I decided to create an all new task and this time I didn't use a batch file at all. Instead I had the task run c:\program Files"\PHP\v7.3\php-win.exe
and then put -f c:\inetpub\wwwroot\osticket\api\cron.php
in the arguments line. That seems to have fixed it so I thought I would share that here in case someone else has a similar issue.
Apart from that, I think it is safe to close this ticket. Thanks!