Workbook disappered after launched

One of my end user contacted me with this problem. After he ran the .exe , entered the activation key, accepted the agreement and pressed ok the file didn’t open and it disappeared form the HD.
He has a Windows 64 bit with Office 32 bit installed.
The exe has been generated for 32 bit so no problem of compatibility.
He has Norton 360 protection. Can it the cause?
Any suggestions?
Thanks

Yes, it looks like a false positive with Norton 360 which has deleted the EXE file. Your customer should add the EXE filepath to the Exception list as explained here: Exclude files or folders from scan https://support.norton.com/sp/en/us/home/current/solutions/kb20100222230832EN_EndUserProfile_en_us

You can also submit your EXE file to Symantec:
https://submit.symantec.com/false_positive/
and they will fix the false positive.
If you agree, we can do it for you too, you have to provide us with the EXE file.

Finally, there are means to avoid false positives: for instance, code signing: see our XLS Padlock user guide