While not certain to fix this scenario, it can't hurt to update the firmware. The latest is here.
You won't lose anything doing the update, and it resolves issues with slow and unresponsive EIP Scans (This may apply)
AFAIK, There are no HP MFP's that print from or Scan to Dropbox directly (May be wrong), they all scan to a dropbox folder shared from a PC, or forward to a software on a PC that relays the scan to dropbox. (Again, may be incorrect here)
Now , with no proxy, and going by the fact you did indeed download the app, and were able to install it, we know your printer has at least some contact with the outside world, so there should be no need to troubleshoot DNS, Gateway, Subnet either.
So if the device is set on HTTPs, make sure the time is correct to less than 3 minutes off real time (easiest is to set it to NTP and use time.nist.gov : 123 with the correct Timezone in the dropdown (Apply > Reboot)
And that will finish troubleshooting Connectivity unless you want to make the primary DNS server 126.96.36.199 just to be cautious from a troubleshooting standpoint.
After that is done, and after the firmware is up to date, and after removal > Reinstall of the dropbox Weblet, I would think a Wireshark trace would be needed to diagnose the issue.
They don't have a proxy in place.
They used to have a HP which worked perfectly, any more ideas?
Does your company use a Proxy to connect to outside websites? The Print and Scan cloud apps require the proxy to be set, if your company requires one.
The steps for setting the Proxy for the device are below.
1.Open an Internet browser on your computer.
2.Enter the IP address of the multifunction printer (MFP) / device. The CentreWare Internet Services page for the MFP opens.
4.Login as Administrator.
5.Under Connectivity, select Setup.
6.Under the Protocol section, for the Proxy Server option, select Edit.
a.Under the HTTP Proxy Server section, select Enabled.
b.Select the Proxy Server address type. The following options are available:
c.Enter in the appropriately formatted address and port number.
d.Select Save. Proxy server settings must be Enabled for Extensible Server Setup. The Connectivity page displays.
7.Under General Setup, select Extensible Service Setup. The Extensible Service Setup page displays.
a.Under Proxy Server, select Proxy from the drop-down list.
b.Under the HTTP, HTTPS section, verify that the proxy is enabled and the proxy information is displayed.
c.Select Apply at the bottom of the page. Proxy server settings apply to features that use HTTP or HTTPS.
d.Select OK to dismiss the pop-up message box.
8.Exit the browser by closing it.
Please let us know if this resolves the connection issue.
Created a Xerox App Gallery Account with no problem.
Added the Device with no problem.
Add the scan and print from Dropbox App with no problem.
The issue is when I click on the app from the front screen I get the below error...
Has anyone came across this the machine i'm working on is a WC7225 with the ConnectKey 2016 build (073.030.075.34540)