how to disallow WB from accessing my data?

[novojil...@gmail.com]

he||o all

when you first login ynu need to allow WB to access your data on SF.

How to block this?

[Ryan Brainard]

The Workbench instance at workbench.developerforce.com accesses your
Salesforce data via OAuth (i.e. Remote Access). From Salesforce Help,
to revoke a previously granted remote application, such as Workbench,
do the following:

In Salesforce, click <Your Name> | Setup | My Personal Information |
Personal Information, and go to the Remote Access section. From there,
click Revoke to revoke the remote access application. After you revoke
the application, the application canno longer use that particular
remote access authorization token toaccess your Salesforce data. You
must revoke all access tokens for a particular application to prevent
it from accessing your Salesforce data.

Please see the full help topic for more info:
https://help.salesforce.com/apex/htviewhelpdoc?id=remoteaccess_request_manage.htm&language=en_US