An example of this full error is:
12/4/2019 1:03:41 PM [Warning]: The remote server returned an error: (401) Unauthorized.
12/4/2019 1:03:41 PM [Response]: {"HttpStatusCode":"401","HttpResponse":"Invalid LocationKey"}
12/4/2019 1:03:41 PM [Response]: [ALOHA-124.9953]: <pos_users_search><HttpStatusCode>401</HttpStatusCode><HttpResponse>Invalid LocationKey</HttpResponse></pos_users_search>
This error can display for the following reasons:
- Aloha Store ID isn't matching between the POS and Punchh
- Firewall/Whitelisting is not configured, blocking the Punchh End Points
- Changes on the Aloha end such as Aloha Version Upgrade, without Punchh being updated as well
Here's how we can rule out these possibilities:
Aloha Store ID isn't matching between the POS and Punchh - In Punchh, the Store ID may be found from Settings>Locations> FInd the location. The Store ID configured will be the first column on the left
If these do not match, the best thing to do is change the Aloha site number if possible. 
Firewall/Whitelisting is not configured, blocking the Punchh End Points. Please see out Firewall requirements here: Aloha Firewall Setup
Changes on the Aloha end such as Aloha Version Upgrade, without Punchh being updated as well - If your site was recently upgraded, or downgraded in Aloha versions, and Punchh was not informed, please reach out to support@punchh.com. Assistance will be necessary from this team to resolve.
If the above options can be ruled out as not causing/resolving the issue, please perform an Uninstall/Reinstall of the Punchh application on the back of house computer.
After doing so, make sure to re-run the PunchhConf.exe to allow for any updates to information to be transferred down.
Disclaimer:
In an effort to supply information as quickly as possible, this article has been published prior to a formal technical review, and is subject to factual, grammatical, and various structural errors. Data may be incomplete, disordered, or incorrect.
This additional disclaimer will be removed upon formal review of this article. The standard Punchh Inc. KB Disclaimer still applies, and can be found at: https://support.punchh.com/hc/en-us/articles/360040100273-Punchh-Inc-Knowledge-Base-Disclaimer