You can get help from the PGAdmin team, http://www.pgadmin.org/support/
---------------------------------------------------------------------------
On Mon, Jan 15, 2018 at 12:56:20PM +0000, PG Bug reporting form wrote:
> The following bug has been logged on the website:
>
> Bug reference: 15011
> Logged by: Carlos Florentino
> Email address: c18florentino@yahoo.com
> PostgreSQL version: 9.6.4
> Operating system: W10 - 1709 x86
> Description:
>
> "The application server could not be contacted!"
>
> pgAdmin 4.2.1
> Local machine
> Server is runnig ok (front end LO Base)
>
> I've found this workaround in SatckOverflow: deleting all entries in
> directory
> ...\AppData\Roaming\pgAdmin\sessions
> This works...
>
> Thank you in advance.
>
>
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ As you are, so once was I. As I am, so you will be. +
+ Ancient Roman grave inscription +