5 Common Mistakes When Using Proxies

Most proxy problems we see in support tickets are not proxy problems at all — they are usage problems that look like proxy problems. Five mistakes account for the vast majority. Avoid them and you will spend less time debugging connection issues and more time getting actual work done.

1. Using free proxies for anything that matters

The free proxy lists scattered across the web are tempting and almost always a bad idea. The proxies on those lists are typically misconfigured servers exposed by accident, abandoned residential routers, or honeypots set up specifically to intercept traffic. The visible problems are obvious — they are slow, frequently offline, and rate-limited everywhere — but the invisible problems are worse.

A free HTTP proxy that you trust with login credentials can log every request, inject malicious JavaScript into responses, or strip TLS in ways your client does not catch. HTTPS through a proxy is end-to-end encrypted only when the proxy honors the CONNECT tunnel correctly; a malicious proxy can man-in-the-middle that handshake if your client does not validate certificates strictly.

Even ignoring security, free proxies fail open in ways that are hard to detect — if the proxy crashes, your traffic silently goes out through your real IP. A scraper that you thought was protected gets your office IP banned, not the proxy’s.

The fix is simple: use a paid provider for anything that matters. The lowest tier of EZProxies shared plans is $0.65 per IP per month, which is essentially the price of avoiding one productive afternoon spent debugging a free proxy.

2. Picking the wrong proxy type for the workload

The three axes — datacenter vs residential, private vs shared, location — trip people up because the answers depend on the workload and not on a universal “best” choice. Common mismatches:

• Using shared IPs for account management. Each account needs its own dedicated IP. Sharing IPs across accounts is the fastest way to get them linked and banned. See account management.
• Using datacenter IPs against sites that fingerprint datacenter ASNs. Most sites do not, but a few aggressive ones (some major retailers, some social platforms) do. If you are getting 403 challenges on every request to a specific target, datacenter may be the wrong tool for that target. See datacenter vs residential.
• Using US IPs to check non-US content. SERPs, pricing, and geo-restricted content all vary by IP location. A US IP querying Google.es gives you Spain-shaped guesses, not the real Spanish results. Spain or Italy plans solve this for European markets.
• Using private IPs for high-volume public-data scraping. Wasteful — shared plans handle this workload at a third of the cost.

The use-case pages walk through specific scenarios with concrete recommendations if you are unsure.

3. Skipping geolocation when it matters

This is a sub-mistake of #2 but common enough to call out separately. Pricing, search results, content licensing, and ad targeting all key off IP geolocation. Running a price-monitoring scraper from US IPs against a French e-commerce site gives you EUR pricing as a US shopper would see it — which is not what most price-monitoring use cases want.

The general rule: if your workload involves anything that varies by country, use IPs in the target country. Price monitoring and SEO monitoring are the most common workloads where this matters; ad verification is a close third.

4. Hammering a single IP at scale

The whole point of buying a pool of proxies is to distribute requests across the IPs so target sites see a normal-looking spread instead of one machine making thousands of requests per minute. Yet a surprising number of scrapers configure proxy pools incorrectly and end up routing 90% of traffic through one IP — usually because of a code bug, a missing rotation step, or a sticky-session configuration that turned out to be sticky for the whole session.

The signs are obvious in hindsight: a single IP gets rate-limited or banned within hours while the other 49 in your pool sit idle. Worth checking before you assume the provider is the problem.

Most scraping frameworks (Scrapy, Playwright, Puppeteer) have built-in proxy rotation; use it. For custom code, the simplest fix is to cycle through your IP list with a counter and modulus, or shuffle and pick the front of the list per request.

5. Misconfigured authentication

The two auth methods — IP whitelist and username/password — each have a failure mode that produces hard-to-debug behavior.

IP whitelist drift: your machine’s public IP changes (mobile hotspot, dynamic ISP, cloud server reboot) and your whitelisted IP no longer matches. The proxy refuses connections with a 407, and from the client’s perspective it looks like the proxy is broken. Easy fix: check the current public IP at ifconfig.me and update the whitelist in the control panel. Better fix: switch to username/password auth for any environment where the source IP changes.

Credential leak: the username/password ends up in a script that gets committed to a public repo or shared in a Slack channel. Anyone with the credentials can use your proxy quota until you notice. Common mitigations: load credentials from environment variables instead of hard-coding, rotate credentials periodically, and use IP whitelist auth where you can to remove credentials from the equation entirely.

If something is broken and you cannot pin down which of these five is the cause, support can usually identify the issue within a few back-and-forth messages.