I cannot access my Explorer folders. The folder symbol now has an additional red symbol as displayed here and I cannot expand those folders to view my project folders and files or perform any action such as download/upload/project creation and similar:

In SDL WorldServer, go to

Management > Asset Interface System > View and Change Properties

and make sure that the attributes Access Control (View), Access Control (Read), Access Control (Write) and Access Control (ACL) are activated as columns. Make sure that the permission to access and write into the Explorer folders/AIS Mounts are set correctly. Here is an example from a Test system:

 

If the permissions are missing or set incorrectly, update them and save your change. If all is set as it should the issue is probably a network problem.

To investigate the problem on the server and network side, first find the directory associated with each AIS folder. In order to do so, go to

Management > Asset Interface System > AIS Mounts

and click on each affected folder/AIS Mount looking like this:

 

The Mount page will open up. Check the directory path: this is where the folder is located on the server where WorldServer is running.
Ask your IT team to to log onto the Application server where WS is running as the user who is running the WorldServer/Idiom Service and then try to access the mount directory point of each 'red mount' 

That will probably fail and it will show that the failure (permissions) are now such that this mount point can not be accessed. 

If that is the case, permissions need to be adjusted in order for the user who is running the WorldServer Services to be able to have read/write and change access to those folders.

The AIS directory on the server where WorldServer is installed is not accessible for the user running the Worlserver. This is most likely a network issue.