> Source: [sk169892](https://support.checkpoint.com/results/sk/sk169892)

# sk169892 - "Invalid Hostname" error in versions R80.40 and higher when any of the reserved words are included in a hostname

| Property | Value |
|----------|-------|
| Solution ID | sk169892 |
| Date Created | 2020-10-06 |
| Last Modified | 2021-10-24 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R81.10 (EOS), R81 (EOS) |
| OS | Gaia |

## Symptoms

- "`Invalid Hostname`" error appears in versions R80.40 and when any of the reserved words listed in [sk40179](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk40179) are included in a hostname.

## Cause

In versions R80.40 and higher, the reserved words in [sk40179](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk40179) also apply to the hostname of the machine.

## Solution

In versions lower than R80.40, the reserved words were allowed in the hostname.  

If one of the reserved words is included in the hostname of a machine, change the hostname before you upgrade to version R80.40 or higher.

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