Registry Settings Lost in Drive Mapping After Dynamics Service Pack

This issue is due to a change in the Windows installer that began in Windows 7.  For systems with UAC turned on, when the install process is run, it is automatically run as the administrator user.  Thus, a separate "user token" is created by the Windows Installer, and no drives that were originally mapped by the current non-administrator user are mapped for the new administrator user.

When CU1 (and other updates) is installed, the installation reads and updates the registry entries for the ParentDirectory and InstallDir.  It attempts to resolve the paths in those registry entries - but the path is invalid since the drive letter mappings have been lost.  Therefore, the registry entries are overwritten, and the values are lost.

To work around this, they can do the following:
To allow the update to be installed correctly:

On the client machine, prior to the installation of the update, open the Command Window as Run as Administrator.
Map the drive to the parent directory using the same drive letter as the original install - e.g.
               
                net use X:  \\servername\installdir

(Note the space between the drive letter and the path.)

The drive letter must match the entry in the registry key for the INSTALLDIR and ParentDirectory entries.
Run the CU1 install.


These steps address the issue if the registry keys were not written correctly (e.g. the steps above were not performed)

Edit the following registry keys:  

HKEY_LOCAL_MACHINE\Software\WOW6432Node\Microsoft\DynamicsSL---> Update  the INSTALLDIR and ParentDirectory entries to the mapped drive path to the SL program files
HKEY_LOCAL_MACHINE\Software\WOW6432Node\Solomon\SolomonIV Tools for Visual Basic -->Update the Parent Directory entry to the mapped drive path to the SL program files

For example if the SL directory is shared on the server and workstation has the S: drive mapped the path would be S:\ApplicationsIf the command prompt is started as "Run as Administrator" and the target drive mapped, then the install succeeds, and the registry entries are properly written.

An alternate solution is to add the following on the client machine:

1. In Registry Editor, locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
2. Right-click Configuration, click New, and then click DWORD (32-bit) Value.
3. Name the new registry entry as EnableLinkedConnections.
4. Double-click the EnableLinkedConnections registry entry.
5. In the Edit DWORD Value dialog box, type 1 in the Value data field, and then click OK.
6. Exit Registry Editor, and then restart the computer.
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This allows the drive mappings to be propagated/"remembered" by the administrator user.

The first option “Net Use S: \\Server\Share” steps were added starting in the SL2015 CU2 Installation Guide since sites were running into issues with the install.