Dear,
Thanks for visiting Microsoft Community. I am happy to help you.
I understand that your Word formulas cannot be converted to professional format and that you have tried many methods.
I noticed that your thread is posted in the English board, but your Office language is not English, you set both your system language and Office language to English to see if you can solve the problem.
There was a user who used this method to solve the problem, you can refer to this thread:
Word公式无法正常转换为专业格式 - Microsoft Community
There is also a Chinese board user who solved the problem by deleting the Word template, you can refer to this thread:
Word公式线性与专业无法互相转化 Inability to Convert Between Linear and Professional - Microsoft Community
The English version of removing Word template is as follows:
Delete word templates
Close all documents, press Windows + R , in the open run box type: %AppData%\Microsoft\Templates, press the enter key.
Backup and delete files with .dotm extension, such as Normal.dotm, and then re-open the word document to try to.
If the above method does not work, you can try the following two methods:
- Cancel the add-ons
Click on the document in the upper left corner of the file - Options - Add-ons - Management of the place to change to COM add-ons, and then select "Go to", uncheck all the add-ons, click OK, restart the word document, look at the effect.
- registry reset office
Press Windows + R, in the open run box, type: regedit, press enter.
Locate the following keys, rename the Office folder (right-click it, select Rename, such as Office renamed Officeold)
HKEY_CURRENT_USER\Software\Microsoft\Office
Please feel free to contact me if you need further assistance.
Best regards
Miyeon.S - MSFT |Microsoft Community Support Specialist