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  • Why Is My File Taking So Long to Process?
Potential Issues

Why Is My File Taking So Long to Process?

Email validationⓘ file processing can take a variable amount of time, depending on how frequently ZeroBounce encounters anti-spam technology during verification. The most common of these is email greylisting. Whenever the email validator encounters greylisting (a 421 response code), it will delay the entire file processing time by up to 35 minutes. Though processing time is extended, ZeroBounce's anti-greylisting technology allows you to obtain more accurate validation results and fewer unknowns.

What is greylisting, and how does it impact email validationⓘ?

Greylisting is an email spam prevention tactic in which mail servers temporarily reject or bounce incoming emails from unknown domains. It's an excellent way to ward off spam messages from email domains that don't have the proper configuration to reattempt delivery.

Many remote mail servers with greylisting will issue a 421 response code initially. Then, after a period (usually up to 30 minutes), they will allow emails to be delivered from the originally greylisted domain. Greylisting is a problem for email validation as it will automatically reject initial attempts to verify an email address.

How does ZeroBounce handle greylisting with email validationⓘ?

To combat this and provide accurate email validation results, ZeroBounce deploys breakthrough anti-greylisting technology. If an email address in your file yields the 421 response code, the email validator delays your processing time by up to 35 minutes to bypass the greylisting. It can then successfully validate the email addresses.

Typically, it takes around one to three hours to validate 100,000 mixed domain email addresses. So, if your file contains 1 million email addresses, you might use math and assume validation will take between 10 and 30 hours.

The good news is that the effects of email greylisting aren't multiplied. A file containing 1 million email addresses will take between three and twenty-three hours to validate, but the average is closer to seven hours.

In addition, there will be little to no wait time to start processing your file. However, it's possible that if many customers submit large files simultaneously, it may create a minor delay before your file begins processing. When ZeroBounce experiences high queue times, the email validation company adds additional servers to compensate for the additional stress. The company uses all resources necessary to care for all customers adequately.

Should I expect long wait times regularly?

ZeroBounce validates email addresses as quickly as technology allows while still providing 99.6% accurate results. Processing times will always be dependent upon the complexity of the uploaded domains and the configuration of those mail servers.

Compare this to many other email validation services that boast high accuracy levels. While some may return your file faster, you'll immediately notice that more of your email addresses have the validation status of "unknown". Unknown results are of no use for your email marketing.

Additionally, ZeroBounce continuously works to improve its email validation and scoring services to provide faster processing while maintaining its superior accuracy levels. All processing times are comparable, if not often faster, than competitor email validation services.

Related Articles

Why do I need a password to open my processed file?

How do I get a password to decrypt my file?

Why is my Overview PDF report blank?

Why are some emails missing append features?

Why do I get the error “unable to expand” with Archive Utility?

Where can I get software to open the CSV file?

Why is my bounce rate high after email cleaning?

Why can’t I find my file on Windows?

Why is the CSV I downloaded incorrectly formatted in Excel?