A backup file is .qbb. A data file is .qbw.

.exe is an executable file. See this blog post: 

Resolution for 'convert exe issue: 'convert exe backup' available: Yes.

The convert exe issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the convert exe issue yourself by looking for a resolution described in the article. If it is a complex convert exe issue or you are unable to solve the issue, you may contact us by clicking here or by using other convert exe support options.

For more information about resolving issues related to convert exe in Quickbooks/QBO or to get support for the issue 'convert exe backup', click the link below:

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