bmc remedy ARERR 90 cannot establish connection

TL;DR

ARERR 90 is a network-layer failure: no TCP connection to the AR System server, so nothing else matters yet. Work it like any connectivity problem, from the client outward: can you reach the host, is the port open, is the server actually listening. Don't touch credentials or workflow config until the connection itself works.

The query

bmc remedy ARERR 90 cannot establish connection

Use this when

• Remedy clients or integrations fail with ARERR 90
• The error appears intermittently
• It starts after a network or server change

Not for

• Remedy authentication failures (different error)
• Form or workflow errors
• Mid-session timeouts (connected, then dropped)

Steps

1. Confirm the server host and port

Read the connection config: server name, port, and whether it expects the portmapper or a direct port. Compare against the server's actual ar.cfg. A wrong port after a server move is the classic trigger.

Expected output: the configured host and port matching the server's ar.cfg.

2. Test basic network reachability

From the failing client, ping the host and test the TCP port. If the port is closed, the problem is network or server-side, not Remedy config. Get the network team involved with this evidence.

Expected output: a successful TCP connection to the AR port, or proof it fails.

3. Check the server is actually up

Confirm the AR System server process is running and listening. After patches and reboots, services sometimes don't come back. The server logs show whether it's accepting connections.

Expected output: the server process running and the port in listening state.

4. Rule out firewalls and proxies

If some clients connect and others don't, a firewall rule or proxy change is blocking the failing ones. Compare a working and failing client's network path hop by hop.

Expected output: identical network treatment for working and failing clients.

Variant phrasings

remedy arerr 90 troubleshooting

Steps 1 through 3 are the connectivity chain in order.

arerr 90 intermittent

Step 4's firewall check; intermittent 90s are usually network, not server.

Why it happens

ARERR 90 sits below everything Remedy-specific: auth, forms, workflow all need a connection first. Because it's numbered like an application error, teams debug it like one, checking passwords and permissions while the packets never arrive. It's a network error wearing an application error's clothes.

Edge cases

• Load-balanced AR servers need all nodes checked. One dead node gives intermittent 90s.
• DNS changes propagate slowly. If the server moved, flush DNS on the clients.
• The portmapper port and the server port are different. Test the right one.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_fdAPSTDNTSieivDHt3QAug