Why is the GUI not loading and throwing this error "REST Error [404]" in Microsoft Office 365 Reporting Add-on for Splunk?

[bradp1234]

I have installed the Microsoft Office 365 Reporting Add-on for Splunk version 1.0.1 on my Heavy Forwarder running Splunk Enterprise version 6.5.2. When I try to go to the Configuration Account page, the page never loads. The error I see in splunkd.log is

03-30-2018 16:35:32.979 +0000 ERROR AdminManagerExternal - Unexpected error "" from python handler: "REST Error [404]: Not Found -- HTTP 404 Not Found -- {"messages":[{"type":"ERROR","text":"Not Found"}]}".  See splunkd.log for more details.

03-30-2018 16:35:32.979 +0000 ERROR AdminManagerExternal - Stack trace from python handler:\nTraceback (most recent call last):\n  File "/opt/splunk/lib/python2.7/site-packages/splunk/admin.py", line 129, in init\n    hand.execute(info)\n  File "/opt/splunk/lib/python2.7/site-packages/splunk/admin.py", line 590, in execute\n    if self.requestedAction == ACTION_LIST:     self.handleList(confInfo)\n  File "/opt/splunk/etc/apps/TA-MS_O365_Reporting/bin/ta_ms_o365_reporting/splunk_aoblib/rest_migration.py", line 38, in handleList\n    AdminExternalHandler.handleList(self, confInfo)\n  File "/opt/splunk/etc/apps/TA-MS_O365_Reporting/bin/ta_ms_o365_reporting/splunktaucclib/rest_handler/admin_external.py", line 40, in wrapper\n    for entity in result:\n  File "/opt/splunk/etc/apps/TA-MS_O365_Reporting/bin/ta_ms_o365_reporting/splunktaucclib/rest_handler/handler.py", line 118, in wrapper\n    raise RestError(exc.status, exc.message)\nRestError: REST Error [404]: Not Found -- HTTP 404 Not Found -- {"messages":[{"type":"ERROR","text":"Not Found"}]}\n

The app was pushed from a deployment server with the name TA-MS_O365_Reporting.

[bradp1234 · Accepted solution]

This error was caused by removing the README folder which contained the spec files. The spec files are needed for the app to work properly.