If you're getting a 401 or 'Invalid credentials' error on the OCI sign-in page, start with the basics: check that you're using the correct tenancy name — it's case-sensitive and easy to mistype. If SSO is configured via IDCS, the issue might be on the identity provider side. Reset your password directly through the Oracle Cloud portal, not through a third-party IdP. Also confirm your account region — logging into us-phoenix-1 when your tenancy lives in eu-frankfurt-1 will just loop you back to an error screen.
Rate limiting hits harder than most expect on free-tier and trial accounts. When requests start bouncing with 429, it means you've exceeded the service limit for that resource type in the region. Check your compartment quotas under Governance → Limits. For 503s, the compute or gateway endpoint may be temporarily overloaded — retry with exponential backoff rather than hammering the endpoint in a loop.
This one has a short checklist:
The OCI dashboard can genuinely lag, especially when listing resources across multiple compartments. Narrow the scope — filter by compartment and region before loading resource lists. Clearing browser cache helps if the UI freezes on the tenancy overview page. Chrome tends to behave better than Firefox for the console.
Large file uploads via the browser console time out above ~1 GB. Use the CLI ('oci os object put') or multipart upload API instead. If the bucket policy restricts public access, make sure your API key has the correct IAM policy attached — 'manage objects in compartment' at minimum. Pre-authenticated request URLs expire, so regenerate them if you're getting 403s on previously working links.