Problems converting xlsx to .xml with XLSForm Offline

So i tried to convert a xlsx form into .xml file using nafundi 1.4and it showed this error.
Input file: C:\Users\user\Desktop\kant\KANTAR_BOOSTER_2022.xlsx

Conversion errors:
'ascii' codec can't decode byte 0x89 in position 269: ordinal not in range(128)

I'm assuming you are using XLSForm Offline? What happens if you try converting the form at https://getodk.org/xlsform. Does it work better?

Yes i tried to convert it with the link you provided. And it works fine with that link. I tried again with the offline converter version 1.4 and it shows the error i mentionet earlier in the post.

XLSForm Offline has reached end-of-life and is no longer being updated supported.

If XLSForm Online at https://getodk.org/xlsform is working for you, I'd recommend you use that. If you need something offlineable, and you are technical, try pyxform.

Hmmm. but how can i collect data through this: https://getodk.org/xlsform
I need to upload a xml file in the odg aggregate to collect data

Download the XML and upload it to Aggregate.

I have 2 questions please.
the first one: the link you provided says XLSForm Online v2.x. so is this the same as using nafundi 2.0 offline converter
the second one: the odk aggregate we are using for the moment before witching to odk central is version 1.4. do you think it will be a problem to upload a .xml file to the odk aggreagte version 1.4

No ODK XLSForm Offline v2.0 was last released in 2020 but the online version is actively maintained so it's not the same.

It depends on your form. ODK Aggregate is no longer actively maintained so there might be something in your form that it won't accept. Just give it a try it won't break anything.