User cannot check-out even though he has Edit rights

The last bit about M-Files Server indicates that you have some sort of automation in place that modifies the document or its metadata immediately after check in. It could be a workflow, an event handler or something managed by Compliance Kit or another add-on. Have you checked whether the version number increases with 1 or 2 when you see this happen? The problem may be related to that although I cannot see how.

For those 2 users it might help to clear the local cache, see https://userguide.m-files.com/user-guide/latest/eng/Clear_local_cache.html

Hi!

I'm sorry, this question was pointless. There were still changes to the NACL going on in the background task, and the user was trying to edit a document that this NACL applies to. But the document he was trying to edit hasn't been yet updated so when he tries to check it out it ofcourse wants to update the NACL, but he does not have the Change Permissions check mark.

About the M-Files Server thing though, the version increments normally by 1. But we do have lots of rules going on in the background, so it's entirely possible that something messes it up.

This is worth reading about the latter point: Audit Trail and Scripting (fixing "(M-Files Server)" in the audit logs), 

Edit 1 hour after comment:

I actually solved it now, without touching the VBScript though. I just removed the Minor Version level in the workflow configuration of Version Control Lite

Hi! Thank you for the link, I've tried many things but due to my limited VBScript knowledge I didn't solve anything yet.

I've found that the culprit is the property "Minor Version", which increments by 1 whenever a document is in the Editable State (version control lite). This started ha

Below is the code set for Minor Version (the code is in the property itself and not in the workflow).

Logic here is that Major Version increments by 1 whenever the document is Released, and Minor increments when editing in Editable State. Major Version however does not have any VBScript. 

Option Explicit

' Set minor version on checkin

' Get Minor Version Value
Dim minorVerValue
minorVerValue = PropertyValues.SearchForProperty(PropertyDef.ID).TypedValue.DisplayValue

' Get current logged in user
' Dim currentUser = Vault.CurrentLoggedInUserID

' if document is in state "In preparation" and User is current user and version is > 1
If (PropertyValues.SearchForProperty(39).TypedValue.GetLookupID = 422 or PropertyValues.SearchForProperty(39).TypedValue.GetLookupID = 405) and CurrentUserID <> -102 and ObjVer.Version > 1 Then

' Increment Minor Version by 1
Dim nextMinorVersion
nextMinorVersion = minorVerValue + 1

' Set minor version property
Output = nextMinorVersion
End If