Issue:

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Error Initiating QBOInit_qwDB(): The 'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine.
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Error initiating ConnectWise Integration the 'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine.
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Error in InitializeOrUseSpellCheck()! Error: ConnOpen() - The 'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine.
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Cause:

Certain component is not installed.

Solution:

With QuoteWerks closed, install this first:

(32 bit version)
https://www.quotewerks.com/download/AccessDatabaseEngine/AccessDatabaseEngine1_x32.EXE

(64 bit version)
https://www.quotewerks.com/download/AccessDatabaseEngine/AccessDatabaseEngine1_x64.EXE 

Then download and install this: https://www.dropbox.com/s/b0lzv0mfk6tbaxs/AccessDatabaseEngine2.exe?dl=1