Problem - How to prevent a user from accessing a specific company folder?
Solution description- In order to prevent a user from accessing a specific company folder, the following steps must be taken:
In the counterparty directory, click Edit. On the Additional Information tab, specify the access group. Save. 
It is necessary to do this for all companies which are to be separated based on groups. Each company will have an access group and when rights are to be given to users, a particular access group can be selected.
Go to Administration – Users.
By right-clicking on the username, select Edit.
Go to the access rights.
The user has several profiles.
By clicking on each profile (it should turn colored), set the type of access to the company groups: choose either all allowed and except (Add the company which needs to be restricted at the restricted value table) or, all restricted in the upper with restrict of value (choose the ones which need to be restricted at the bottom)
Every user profile should be given similar settings and once done, click save and close.
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