A simple ACMEv2 client for Windows (for use with Let's Encrypt et al.)


Run an external script or program to create or update the validation records.


A script to create the DNS record must be provided. The arguments passed to the script will be create {Identifier} {RecordName} {Token} by default, where the following replacements are made by win-acme:

Value Replaced with  
{Identifier} host name that’s being validated, e.g.  
{RecordName} full name of the TXT record that is being expected, e.g.  
{ZoneName} registerable domain, e.g.  
{NodeName} registerable domain, e.g. _acme-challenge.sub  
{Token} content of the TXT record, e.g. DGyRejmCefe7v4NfDGDKfA  

The order and format of arguments may be customized by providing a diffent argument string. For example if your script needs arguments like:

--host --token DGyRejmCefe7v4NfDGDKfA

…your argument string should like like this:

--host {RecordName} --token {Token}


Optionally, another script may be provided to delete the record after validation. The arguments passed to the script will be delete {Identifier} {RecordName} {Token} by default. The order and format of arguments may be customized by providing a diffent argument string, just like for the create script. You can also choose to use the same script for create and delete, with each their own argument string.


You can use --dnsscriptparallelism to specify if your script supports parallelism. This only has any effect when DisableParallelism is set to false in settings.config. You may use the following values:

Value Meaning
0 Serial, default serial behaviour
1 Allow multiple new records to created as the same time. Only do this when you are sure that a “create” request will not interfere with others running at the same time
2 Allow multiple validations to run at the same time. This is possible in theory with any DNS provider, but you must be sure that your script is non-destructive, e.g. it should not overwrite pre-existing TXT records, nor delete more than the one specifically asked for
3 Combination of 1 and 2


A lot of good reference scripts are available from the POSH-ACME project. Note that these scripts are not compatible with win-acme. You will have to make changes (e.g. in terms of accepted parameter and such) in order to use them.


  • Create script only

    -validationmode dns-01 --validation script --dnscreatescript c:\create.ps1 [--dnscreatescriptarguments {args}]

  • Create and delete scripts seperate

    -validationmode dns-01 --validation script --dnscreatescript c:\create.ps1 --dnsdeletescript c:\delete.ps1 [--dnscreatescriptarguments {args}] [--dnsdeletescriptarguments {args}]

  • Create-delete script (integrated)

    -validationmode dns-01 --validation script --dnsscript c:\create-and-delete.ps1 [--dnscreatescriptarguments {args}] [--dnsdeletescriptarguments {args}]