Notes client will not install from a hidden share

Why is is not possible to install the Notes client (801 or 802) from a hidden network share? Within the MSI InstallExecuteSequence section there is a check for valid characters in the install path (CheckLocForValidCharsExec.5F3129E8_3AD4_4346_AEE6_A314E2DE64D9). What’s the point of this?

A work around is to copy the install files to the client or map a drive to the hidden share but I wonder how many other people have wasted a day working out why the install fails to install from a hidden network share?

Error from MSI log file:

GenerateInfo/CheckLocationForValidCharsExecute: ERROR - Invalid directory location:

\/Saferoot$/Program/Common/NotesClient/802

The specified directory location cannot contain non-ASCII characters or any of the following characters:

" ; | * ? < > ! # & $ ` , ’ = ^ @