If you want to know how you can check the properties & file extensions, then call on the QuickBooks Online Support Phone Number. The IT professionals will let you know some relevant steps.
● Open the folder where you have saved your company file.
● Now right click on the company file & choose the properties.
● Ensure the type of file is QB company file & the file size should be 7MB.
● Then, click on the advanced & ensure that boxes for compress & encrypt attributes are not checked.