Issue: When distributing App-V 4.5 standalone packages to a 4.5 Application Virtualization Client machine, packages seem to disappear from the App-V Client Management console. The icons disappear from the SoftGrid Menu and Desktop as well. You may also see this error messages after installing a new package:

[03/25/2007 23:50:28.544 INTF WRN] {tid=2080:usr=username}
The data directory for this user is already in use by another user with SID
S-1-5-18-xxxxxxx-. All users must have unique data directories. The
UserDataDirectory setting in the registry may be configured incorrectly.

Cause:  This can occur if you inadvertently create packages with the same package GUID.  If this happens, when a new App-V package with the same GUID is installed it effectively overwrites (removes) any package with the same package GUID installed previously. […]

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