"HTTP Error 503. The service is unavailable" then browsing to /ECP "exchange 2019"

Question

Hi
Migrating from exchange 2016 to 2019.

Exchange host 2019: elemsex01

I get "HTTP Error 503. The service is unavailable" when browsing to:

• Hostname correct certificate: https://elemsex01.corp.elevation.se/ecp/
• Local host: https://localhost/ecp/
• DNS record: https://remote.corp.elevation.se/ecp/

I have read all threads and blogs I can finned but nothing is helping me.

Do someone have any idea how I can continue my trouble shooting?

//marsk

Answer 1

Hi Martin,

I ran into similar issue when we installed a windows update. the errors were as below.

1. users would get the error "Fix Exchange HTTP Error 503. The Service is Unavailable" when trying to access email via OWA
2. Outlook Clients wont connect to the exchange server

****Resolution:****

1. Open “ISS Manager”, Type “inetmgr” in “RUN” and select Default Web Settings and Open “Edit Binding option”It is vital to provide the correct Exchange Certificates to the ports
2. as there are two parts of IIS in exchange 2013 onwards i.e. Exchange Frontend and Exchange Backend
3. first I verified that the SSL corticates bindings with the correct SSL certificate were present.
4. Than I looked at the Exchange Bank End home and found that there were no certificate bindings for port 444
5. Selected the Microsoft Exchange Server ( self generated default Certificate by the exchange Server) do not use the third party CA to bind in this location
6. as soon as this was selected OWA/ECP and outlook clients started working fine.

I hope this helps.

Many Thanks

Bilal

Answer 2

@Martin Skorvald
Hi,

Sorry I need to ask several questions in order to get some more information:

1. Can you see the login page? If you can,was the administrator account on the Exchange 2016 server and you powered the Exchange 2016 server off?
2. Are you able to access OWA?
3. What suggestions have you tried so far? Did you try the following ones?
   (1)check the certificates bindings of Default Web Site and Exchange Back End in IIS manager.
   (2)check if the MSExchangeECPapppool stops or recycle the MSExchangeECPapppool.
4. Did you find some relevant error messages in the application log?

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Answer 3

sorry if i'm a bit short in my answer.
A hectic day.

I only get "HTTP Error 503. The service is unavailable" then i hit the IIS on the Exchange 2019.
No log on page acure, not for ECP och webmail.
It doesn't matter if the exchange 2016 server is on or off.
The App and system logs is empty, nothing that can be related to IIS/Exchange.

Do to that i'm with in the domain, I have generated a certificate from the domain CA.
The root certificate for this CA is trusted in all machines that I use.
The app pool has been recycled.

//marsk

Answer 4

Yes, I think my certificate is in the right place.

!

Answer 5