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1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errorsIf WordPress shows “Server Not Found” immediately after a hosting move, check DNS before changing WordPress files. Your domain is probably still resolving to the old server, a test address saved in your computer’s hosts file, or no valid address at all. Confirm the public nameservers and A record, remove any local override, flush DNS caches, and keep the old host online until the new copy works.
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This guide takes you through that order, then covers WordPress URL settings, SSL, caching, and safeguards for the next migration.
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What “Server Not Found” means after a host change
When someone enters your domain, the browser first asks a DNS resolver for an IP address. The resolver follows the domain’s nameserver and record configuration, returns an address, and the browser connects to the server at that address. A hosting move is incomplete until that chain points to the new infrastructure.
During migration, several different situations can produce the same browser message:
- The registrar still delegates the domain to the old host’s nameservers.
- The nameservers are correct, but the A record still contains the old server IP.
- An old A, AAAA, or CNAME record conflicts with the new record.
- Your computer’s hosts file forces the domain to an old or temporary IP.
- A local DNS cache continues returning the previous answer.
- The domain resolves correctly, but WordPress, a domain-mapping plugin, a cache layer, or SSL configuration routes the request incorrectly.
Because a hosts-file entry and a public DNS record are separate, one computer can fail while another device loads the site normally. That is why testing from a second network is one of the first checks.
Run this triage sequence first
- Test outside the affected connection. Open the domain on a phone using cellular data, or on another network. If it works there, concentrate on the original computer’s hosts file and DNS cache. If it fails everywhere, inspect public DNS and the new server.
- Check the hosts file. Look for your domain and any
wwwvariant mapped to an old, staging, or guessed IP. Delete those lines after confirming public DNS is ready. Save the file without changing unrelated entries. - Flush the local DNS cache. On Windows, open Command Prompt as an administrator and run
ipconfig /flushdns. On macOS, runsudo dscacheutil -flushcache, thensudo killall -HUP mDNSResponder. On Linux systems using systemd-resolved, runsudo resolvectl flush-caches(the equivalent command varies by distribution). Restart the browser or test in a private window. - Compare local and public answers. Use a DNS lookup or worldwide propagation checker for the root domain and
www. Check the returned nameservers, A record, and, if present, AAAA record. A checker showing the new value broadly is useful evidence, but it cannot guarantee that every resolver, device, or ISP has refreshed. - Verify the registrar and DNS zone. Make sure the registrar’s nameserver setting is the one supplied by the new host, then inspect the active DNS zone for the correct A record and any required
wwwCNAME. Remove stale records that still point at the old provider. - Leave the old host available while testing. Do not delete the old site or remove its domain assignment until the new copy has passed your checks. If a backup or database import is incomplete, taking down the old host can turn a recoverable migration problem into a full outage.
Inspect the hosts file for a hidden override
The hosts file is a local, plain-text list that maps names directly to IP addresses. It overrides public DNS on that one machine. Migration tutorials often recommend adding a temporary line so you can preview the new server; forgetting to remove it is a common cause of “server not found” or an outdated site after the DNS cutover.
Windows
Open Notepad as administrator, choose File > Open, and browse to C:WindowsSystem32driversetchosts. Change the file-type filter to show all files. Remove or comment out lines containing your domain or www that reference the old or test IP, save, flush DNS, and retry.
macOS and Linux
Open /etc/hosts with an editor using administrator privileges, for example sudo nano /etc/hosts. Delete only the migration entries for your domain, save, flush the cache, and test again. Keep standard localhost and system entries intact.
Use the result diagnostically
If removing the entry fixes the site, your public DNS may already be correct; the failure was local. If it does not, continue with the public DNS checks rather than repeatedly editing the hosts file.
Confirm nameservers and records at the right provider
DNS can be managed at the registrar, the old host, the new host, or a separate DNS service. The nameservers shown at the registrar determine which zone is authoritative. Editing records in a non-authoritative panel has no effect.
| Item | What to verify | Typical migration mistake |
|---|---|---|
| Authoritative nameservers | The registrar lists the nameservers for the DNS service you intend to use. | Nameservers still point to the old host, so edits in the new host’s panel are ignored. |
| Root A record | The apex domain resolves to the new server’s IPv4 address. | The old server IP remains, or two competing A records send visitors to different servers. |
www record |
The www hostname has the intended CNAME or A record and follows your chosen canonical domain. |
www still targets the old host while the root domain targets the new one. |
| AAAA record | If the new host supports IPv6, the AAAA value is valid; otherwise remove a stale value. | IPv6-capable devices follow an old AAAA record while IPv4 users reach the new server. |
| Other aliases | Review CNAMEs for staging, mail, or application subdomains. | A leftover alias redirects web traffic to a retired service. |
Do not add random records to “make DNS propagate.” Record the intended final state first, then remove conflicts. DNS caches honor each record’s TTL, so different networks can legitimately return different answers for a while after a change. There is no universal propagation deadline that guarantees every resolver will update at the same moment.
Test the new server before and after cutover
Keep the old host online until you have verified the new files, database, PHP version, permalink behavior, forms, media, and administrative login. Test both the bare domain and www, and test the HTTP-to-HTTPS redirect you intend to use.
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When the old site still appears
An old page usually means DNS is still returning the previous IP, not that WordPress “reverted.” Compare the IP shown by a lookup on the affected device with the new server’s address. If only one network is old, wait for that resolver’s cache while continuing to serve both hosts safely.
When the new site shows a fatal error
Do not remove the old host merely because DNS has been changed. A failed database import, missing PHP extension, incorrect file permissions, or an incomplete domain assignment can make the new copy fail. Restore service from the old host while you correct the new environment, then repeat testing.
Check WordPress’s own domain settings
Once DNS reaches the new server, WordPress must generate URLs for the same hostname and protocol that visitors use. In the dashboard, go to Settings > General and check WordPress Address (URL) and Site Address (URL). They should use the intended domain, including https:// if SSL is active, with no accidental staging subdomain, extra path, or spelling difference.
Save only after confirming the new domain resolves. A wrong value can redirect every request to an unreachable address and lock you out of the dashboard. If you cannot reach the dashboard after a mistaken change, use your host’s documented recovery method for editing the stored WordPress options, and take a database backup before changing them.
Domain mapping, cache, and redirect plugins
Migration-related plugins can retain the old hostname, force a staging URL, or cache redirects. Temporarily disable domain-mapping, redirect, and page-cache features while diagnosing, then re-enable them one at a time after the canonical URL works. Clear the plugin cache after each domain change.
Rule out SSL and protocol problems
DNS can be correct while HTTPS is not. Test http://your-domain and https://your-domain separately. If HTTP loads but HTTPS fails, the new server may not yet have a certificate for the root and www names, or the certificate may be installed on the wrong virtual host. If HTTPS loads but loops between HTTP and HTTPS, check the site URL, server redirect rules, and any SSL-enforcement plugin so only one layer performs the redirect.
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Do not judge certificate readiness from one browser alone. Test a private window and a second network after installing the certificate, and clear cached redirects only after the server presents the correct certificate.
Use symptoms to choose the next check
| Symptom | Most likely area | Next action |
|---|---|---|
| Only one computer fails | Hosts file or local DNS cache | Remove old mappings, flush DNS, and retry from another network. |
| Every network reaches the old site | Nameservers or A record | Confirm the registrar’s authoritative nameservers and the active zone’s root record. |
Root domain works but www fails |
Separate www record or certificate |
Correct the CNAME/A record and include www in SSL coverage. |
| Some networks work and others fail | Resolver caching or conflicting records | Compare lookup results and remove stale A, AAAA, or CNAME values. |
| DNS resolves but WordPress redirects elsewhere | WordPress URL or plugin configuration | Check both General Settings URLs and disable migration-related redirects temporarily. |
| DNS resolves but the browser reports a certificate error | SSL installation or HTTPS routing | Install a certificate for every hostname and verify the HTTPS virtual host. |
Prepare the next migration to avoid the outage
Lower the DNS TTL in advance
Reduce the relevant record’s TTL well before a planned move so cached answers expire sooner. The exact lead time depends on the previous TTL and resolver behavior; changing it immediately before the cutover cannot retroactively clear caches that already stored the longer value.
Preview with a hosts-file entry
Before changing public DNS, map the domain temporarily to the new server’s IP in your hosts file. Test the production hostname against the new copy, including login, permalinks, uploads, forms, cron jobs, redirects, and HTTPS. Remove the entry after the preview so your machine follows public DNS like ordinary visitors.
Keep a rollback path
Take a fresh database and file backup, document the old and new IP addresses, and keep the old host serving the verified site until the new environment is stable. Change DNS only after the backup restores successfully and the new host has the required PHP, database, storage, and SSL configuration.
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Write down the authoritative nameservers, root A or AAAA records, www behavior, mail records, and any CDN or subdomain aliases. This prevents a later cleanup from deleting a record that another service still needs.
When to contact support
Contact the registrar when the nameserver delegation does not match your intended DNS provider. Contact the DNS provider when records in the authoritative zone return unexpected values or cannot be edited. Contact the new host when DNS resolves to its IP but it returns no site, the wrong virtual host, a connection refusal, or an incomplete SSL certificate. Provide the exact domain, the lookup results, the time of the change, and whether the failure occurs on multiple networks; that information lets support distinguish DNS from server configuration quickly.
Once the hosts file is clean, local caches are flushed, authoritative records point to the new server, WordPress URLs match the live domain, and SSL and plugins are aligned, “Server Not Found” normally disappears without reinstalling WordPress.
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