# $mid(%\_file\_mod\_datetime%,5,4)

**URL:** https://community.mp3tag.de/t/mid-file-mod-datetime-5-4/13307
**Category:** Support
**Created:** [April 8, 2012, 3:46pm UTC](https://community.mp3tag.de/t/mid-file-mod-datetime-5-4/13307 "2012-04-08T15:46:15Z")
**Posts on this page:** 1
**Showing post:** 4

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### Author: ![DetlevD](https://community.mp3tag.de/user_avatar/community.mp3tag.de/detlevd/32/123_2.png) [@DetlevD](https://community.mp3tag.de/u/DetlevD)
#### Post date: [April 8, 2012, 4:38pm UTC](https://community.mp3tag.de/t/mid-file-mod-datetime-5-4/13307/4 "2012-04-08T16:38:26Z")

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> [@Denis Bisson](#):
>
> ... I am sure you're very good and it's my fault if I don't understand ... Are you explaining it's normal? Am I doing something wrong? ...

%\_file\_mod\_datetime% returns a text string, which contain some characters not to be allowed to be used in the file sytem.  
The "Tag-Filename" preview removes such forbidden characters automatically, that's all.  
I tend to say it is not a heavy bug.

But there might be a quirk in the sequence of applying the validating rule.  
See there ...  
[Converter Tag - Filename validates part of format string before applying other functions around](https://community.mp3tag.de/t/12727/1)

DD.20120408.2058.CEST

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