pgAdmin v4: The application server could not be contacted.

[lepluc]

I'm new to PostgresSQL and to this list! I have installed version 10 64-bit (on Windows 7) I also used stackbuilder to install the ODBC drivers. The SQL shell allows me to logon to the server as postgres but when starting pgAdmin I get: The application  server could not be contacted. This a fatal error of course..... Any hint, tips or "Oh man you should have...." etc will be greatly appreciated.

/Richard

[dhananjayjejur]

Hi lepluc,

Can you check the required pg_hba.conf entry is present for pgAdmin4. 

Also if this is not the issue then, Can you please share the FATAL error which you are receiving?

Hope this helps.

-Regards 

Dhananjay 

[lepluc]

Hi  and thanks for the answer.

Well there is a file pg_hba.conf in the istallation, but not in the pgAdmin 4 subdirectory. The fatal error is a message box with the caption "Fatal Error" and the message "The application server could not be contacted." 

Regards

/Richard

[kapil]

Hi lepluc,

The issue which you are facing may be solved by below workarounds listed below.

1) Start pgAdmin 4 using administrator.

Steps:
1. Right click pgAdmin 4 icon 
2. Select "Run As Administrator"

2) If running the pgadmin 4 by Administrator is not helpful in your case then try clearing out the "C:\Users\{YourUser}\AppData\Roaming\pgAdmin" folder. I believe it was attempting to use the sessions from the prior version and was failing.

Note: AppData\Roaming\pgAdmin is a hidden folder.

Hope this helps you.

[kapil]

Hi lepluc,

Please let us know with your feedback that your able to resolve this issue.

[lwbaqueros]

Hello. I had the same problem. I deleted the folder and then PGAdmin open normally from Web

[kapil]

Hi lwbaqueros,

Thank you for the update. Glad to hear that issue which your facing as been resolved.

Please let us know if you need any other help/Information.

[Kmete]

Hi, I have the same problem but I use PostgreSQL 10.5-24.1C on Windows Server 2012 R2 Standard.

may be need any actions after installing db? And I have forgotten something to do...

[kapil]

Hi Kmete,

The issue which you are facing may be solved by below workarounds listed below.

1) Start pgAdmin 4 using administrator.

Steps:
1. Right click pgAdmin 4 icon 
2. Select "Run As Administrator"

2) If running the pgadmin 4 by Administrator is not helpful in your case then try clearing out the "C:\Users\{YourUser}\AppData\Roaming\pgAdmin" folder. I believe it was attempting to use the sessions from the prior version and was failing.

Note: AppData\Roaming\pgAdmin is a hidden folder.

Hope this helps you.

[ayushgarg]

Hi

I have tried both of these methods, but still pgAdmin is not opening.

[sachinfate]

Hi Ayush,

Could you please reinstall the pgAdmin v4 and then try to access it.

[ayushgarg]

Thanks for your reply.
I don't know how but it has started working, so I won't touch it.