Convert command from Certutil to Powershell

[JackStuart]

Converting from using Certutil to get a SHA256 to the Powershell Get-FileHash

[learn-build-service-prod]

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defender-office-365/tenant-allow-block-list-files-configure.md	✅Succeeded

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[chrisda]

@JackStuart, may I ask why? That DOS-based procedure is used elsewhere, so if we change this one, I'd like to change any others.

[JackStuart]

Hi @chrisda,

I feel like it's more consistent to update the command from Certutil to PowerShell, as the rest of the doco references PowerShell, including the line immediately above. It doesn't make a lot of sense to open Command Prompt and run certutil solely to get a SHA256, especially when there’s a native PowerShell option available. If it was something more complicated than sure. But I think PS is the best option here

There are 2 other places that Certutil is specifically used to get a SHA256. To me it would make sense to also update them to Powershell as a more native way of doing things

defender-docs/defender-office-365/threat-explorer-real-time-detections-about.md

Line 1227 in 1719f7d

|SHA256|Integer. Separate multiple values by commas. <br/><br/> To find the SHA256 hash value of a file in Windows, run the following command in a Command Prompt: `certutil.exe -hashfile "<Path>\<Filename>" SHA256`.|✔|✔|

defender-docs/defender-office-365/campaigns.md

Line 186 in 1719f7d

|Attachment SHA256|Text. Separate multiple values by commas. <br/><br/> To find the SHA256 hash value of a file in Windows, run the following command in a Command Prompt: `certutil.exe -hashfile "<Path>\<Filename>" SHA256`.|