Error in PowerShell: String Length cannot be zero

### What You Are Seeing?
I cannot use certain features such as `install` and `upgrade` due to a String Length problem. The error message states that the "string length cannot be zero parameter : variable" (The original error message is in Korean, this is a translated version).

### What is Expected?
`choco install { package name }` is supposed to install a package.

### How Did You Get This To Happen? (Steps to Reproduce)
Downloaded Chocolatey 0.10.15 via PowerShell Script in Admin Mode and immediately started `choco install git`.
Also tried every single installation from version 0.10.10, every single time this happens.

### Issue reproduction

1. Install Chocolatey (by whatever means you want)
2. Open Registry Editor
3. Navigate to `HKCU\Environment` (or `HKLM\Environment`)
4. Edit `(Default)` key to include anything (or leave it blank)
5. Attempt to run `choco install ` where `` is the name of any package.
6. Receive error that `String Length cannot be zero`

### Output Log

Full Log Output

~~~sh
2019-10-07 17:07:32,136 32020 [INFO ] - Chocolatey v0.10.15
2019-10-07 17:07:32,150 32020 [DEBUG] - Chocolatey is running on Windows v 10.0.17763.0
2019-10-07 17:07:32,160 32020 [DEBUG] - Attempting to delete file "C:/ProgramData/chocolatey/choco.exe.old".
2019-10-07 17:07:32,162 32020 [DEBUG] - Attempting to delete file "C:\ProgramData\chocolatey\choco.exe.old".
2019-10-07 17:07:32,171 32020 [DEBUG] - Command line: "C:\ProgramData\chocolatey\choco.exe" install -dv git
2019-10-07 17:07:32,179 32020 [DEBUG] - Received arguments: install -dv git
2019-10-07 17:07:32,285 32020 [DEBUG] - RemovePendingPackagesTask is now ready and waiting for PreRunMessage.
2019-10-07 17:07:32,292 32020 [DEBUG] - Sending message 'PreRunMessage' out if there are subscribers...
2019-10-07 17:07:32,303 32020 [DEBUG] - [Pending] Removing all pending packages that should not be considered installed...
2019-10-07 17:07:32,355 32020 [WARN ] - [Pending] Removing incomplete install for 'git.install'
2019-10-07 17:07:32,489 32020 [DEBUG] - Performing validation checks.
2019-10-07 17:07:32,497 32020 [DEBUG] - Global Configuration Validation Checks:
2019-10-07 17:07:32,504 32020 [DEBUG] - - Package Exit Code / Exit On Reboot = Checked
2019-10-07 17:07:32,509 32020 [DEBUG] - System State Validation Checks:
2019-10-07 17:07:32,523 32020 [DEBUG] - Reboot Requirement Checks:
2019-10-07 17:07:32,530 32020 [DEBUG] - - Pending Computer Rename = Checked
2019-10-07 17:07:32,548 32020 [DEBUG] - - Pending Component Based Servicing = Checked
2019-10-07 17:07:32,556 32020 [DEBUG] - - Pending Windows Auto Update = Checked
2019-10-07 17:07:32,569 32020 [DEBUG] - - Pending File Rename Operations = Ignored
2019-10-07 17:07:32,586 32020 [DEBUG] - - Pending Windows Package Installer = Checked
2019-10-07 17:07:32,603 32020 [DEBUG] - - Pending Windows Package Installer SysWow64 = Checked
2019-10-07 17:07:32,620 32020 [INFO ] - 2 validations performed. 2 success(es), 0 warning(s), and 0 error(s).
2019-10-07 17:07:32,633 32020 [DEBUG] - The source 'https://chocolatey.org/api/v2/' evaluated to a 'normal' source type
2019-10-07 17:07:32,647 32020 [DEBUG] -
NOTE: Hiding sensitive configuration data! Please double and triple
check to be sure no sensitive data is shown, especially if copying
output to a gist for review.
2019-10-07 17:07:32,687 32020 [DEBUG] - Configuration: CommandName='install'|
CacheLocation='C:\Users\thekp\AppData\Local\Temp\chocolatey'|
ContainsLegacyPackageInstalls='True'|
CommandExecutionTimeoutSeconds='2700'|WebRequestTimeoutSeconds='30'|
Sources='https://chocolatey.org/api/v2/'|SourceType='normal'|
Debug='True'|Verbose='True'|Trace='False'|Force='False'|Noop='False'|
HelpRequested='False'|UnsuccessfulParsing='False'|RegularOutput='True'|
QuietOutput='False'|PromptForConfirmation='True'|AcceptLicense='False'|
AllowUnofficialBuild='False'|Input='git'|AllVersions='False'|
SkipPackageInstallProvider='False'|PackageNames='git'|
Prerelease='False'|ForceX86='False'|OverrideArguments='False'|
NotSilent='False'|ApplyPackageParametersToDependencies='False'|
ApplyInstallArgumentsToDependencies='False'|IgnoreDependencies='False'|
AllowMultipleVersions='False'|AllowDowngrade='False'|
ForceDependencies='False'|Information.PlatformType='Windows'|
Information.PlatformVersion='10.0.17763.0'|
Information.PlatformName='Windows 10'|
Information.ChocolateyVersion='0.10.15.0'|
Information.ChocolateyProductVersion='0.10.15'|
Information.FullName='choco, Version=0.10.15.0, Culture=neutral, PublicKeyToken=79d02ea9cad655eb'|

Information.Is64BitOperatingSystem='True'|
Information.Is64BitProcess='True'|Information.IsInteractive='True'|
Information.UserName='thekp'|
Information.UserDomainName='DESKTOP-8H6K68F'|
Information.IsUserAdministrator='True'|
Information.IsUserSystemAccount='False'|
Information.IsUserRemoteDesktop='False'|
Information.IsUserRemote='True'|
Information.IsProcessElevated='True'|
Information.IsLicensedVersion='False'|Information.LicenseType='Foss'|
Information.CurrentDirectory='C:\WINDOWS\system32'|
Features.AutoUninstaller='True'|Features.ChecksumFiles='True'|
Features.AllowEmptyChecksums='False'|
Features.AllowEmptyChecksumsSecure='True'|
Features.FailOnAutoUninstaller='False'|
Features.FailOnStandardError='False'|Features.UsePowerShellHost='True'|
Features.LogEnvironmentValues='False'|Features.LogWithoutColor='False'|
Features.VirusCheck='False'|
Features.FailOnInvalidOrMissingLicense='False'|
Features.IgnoreInvalidOptionsSwitches='True'|
Features.UsePackageExitCodes='True'|
Features.UseEnhancedExitCodes='False'|
Features.UseFipsCompliantChecksums='False'|
Features.ShowNonElevatedWarnings='True'|
Features.ShowDownloadProgress='True'|
Features.StopOnFirstPackageFailure='False'|
Features.UseRememberedArgumentsForUpgrades='False'|
Features.IgnoreUnfoundPackagesOnUpgradeOutdated='False'|
Features.SkipPackageUpgradesWhenNotInstalled='False'|
Features.RemovePackageInformationOnUninstall='False'|
Features.ExitOnRebootDetected='False'|
Features.LogValidationResultsOnWarnings='True'|
Features.UsePackageRepositoryOptimizations='True'|
Features.ScriptsCheckLastExitCode='False'|
ListCommand.LocalOnly='False'|
ListCommand.IdOnly='False'|ListCommand.IncludeRegistryPrograms='False'|
ListCommand.PageSize='25'|ListCommand.Exact='False'|
ListCommand.ByIdOnly='False'|ListCommand.ByTagOnly='False'|
ListCommand.IdStartsWith='False'|ListCommand.OrderByPopularity='False'|
ListCommand.ApprovedOnly='False'|
ListCommand.DownloadCacheAvailable='False'|
ListCommand.NotBroken='False'|
ListCommand.IncludeVersionOverrides='False'|
UpgradeCommand.FailOnUnfound='False'|
UpgradeCommand.FailOnNotInstalled='False'|
UpgradeCommand.NotifyOnlyAvailableUpgrades='False'|
UpgradeCommand.ExcludePrerelease='False'|
NewCommand.AutomaticPackage='False'|
NewCommand.UseOriginalTemplate='False'|SourceCommand.Command='unknown'|
SourceCommand.Priority='0'|SourceCommand.BypassProxy='False'|
SourceCommand.AllowSelfService='False'|
SourceCommand.VisibleToAdminsOnly='False'|
FeatureCommand.Command='unknown'|ConfigCommand.Command='unknown'|
ApiKeyCommand.Remove='False'|PinCommand.Command='unknown'|
OutdatedCommand.IgnorePinned='False'|Proxy.BypassOnLocal='True'|
2019-10-07 17:07:32,780 32020 [DEBUG] - _ Chocolatey:ChocolateyInstallCommand - Normal Run Mode _
2019-10-07 17:07:32,790 32020 [INFO ] - Installing the following packages:
2019-10-07 17:07:32,829 32020 [INFO ] - git
2019-10-07 17:07:32,834 32020 [INFO ] - By installing you accept licenses for the packages.
2019-10-07 17:07:33,051 32020 [DEBUG] - Using 'https://chocolatey.org/api/v2/'.
2019-10-07 17:07:33,474 32020 [DEBUG] - - Supports prereleases? 'True'.
2019-10-07 17:07:33,484 32020 [DEBUG] - - Is ServiceBased? 'True'.
2019-10-07 17:07:33,885 32020 [DEBUG] - Package 'git' found on source 'https://chocolatey.org/api/v2/'
2019-10-07 17:07:33,980 32020 [INFO ] - [NuGet] Attempting to resolve dependency 'git.install (= 2.23.0)'.
2019-10-07 17:07:37,668 32020 [INFO ] - [NuGet] Attempting to resolve dependency 'chocolatey-core.extension (≥ 1.3.3)'.
2019-10-07 17:07:37,744 32020 [INFO ] - [NuGet] Attempting to resolve dependency 'chocolatey (≥ 0.10.7)'.
2019-10-07 17:07:39,790 32020 [INFO ] - [NuGet] Installing 'git.install 2.23.0'.
2019-10-07 17:07:39,830 32020 [DEBUG] - [NuGet] Added file 'LICENSE.txt' to folder 'git.install\legal'.
2019-10-07 17:07:39,842 32020 [DEBUG] - [NuGet] Added file 'VERIFICATION.txt' to folder 'git.install\legal'.
2019-10-07 17:07:39,854 32020 [DEBUG] - [NuGet] Added file 'chocolateyInstall.ps1' to folder 'git.install\tools'.
2019-10-07 17:07:40,260 32020 [DEBUG] - [NuGet] Added file 'Git-2.23.0-32-bit.exe' to folder 'git.install\tools'.
2019-10-07 17:07:40,669 32020 [DEBUG] - [NuGet] Added file 'Git-2.23.0-64-bit.exe' to folder 'git.install\tools'.
2019-10-07 17:07:40,682 32020 [DEBUG] - [NuGet] Added file 'helpers.ps1' to folder 'git.install\tools'.
2019-10-07 17:07:40,802 32020 [DEBUG] - [NuGet] Added file 'git.install.nupkg' to folder 'git.install'.
2019-10-07 17:07:41,158 32020 [DEBUG] - [NuGet] Added file 'git.install.nuspec' to folder 'git.install'.
2019-10-07 17:07:41,162 32020 [INFO ] - [NuGet] Successfully installed 'git.install 2.23.0'.
2019-10-07 17:07:41,166 32020 [INFO ] -
git.install v2.23.0 [Approved]
2019-10-07 17:07:41,186 32020 [INFO ] - git.install package files install completed. Performing other installation steps.
2019-10-07 17:07:41,267 32020 [ERROR] - git not installed. An error occurred during installation:
문자열의 길이는 0일 수 없습니다.
매개 변수 이름: variable
2019-10-07 17:07:41,272 32020 [INFO ] - git package files install completed. Performing other installation steps.
2019-10-07 17:07:41,274 32020 [DEBUG] - No package information as package is null.
2019-10-07 17:07:41,285 32020 [DEBUG] - No package information to save as package is null.
2019-10-07 17:07:41,297 32020 [DEBUG] - Sending message 'HandlePackageResultCompletedMessage' out if there are subscribers...
2019-10-07 17:07:41,302 32020 [ERROR] - The install of git was NOT successful.
2019-10-07 17:07:41,306 32020 [ERROR] - git not installed. An error occurred during installation:
문자열의 길이는 0일 수 없습니다.
매개 변수 이름: variable
2019-10-07 17:07:41,319 32020 [WARN ] -
Chocolatey installed 1/2 packages. 1 packages failed.
See the log for details (C:\ProgramData\chocolatey\logs\chocolatey.log).
2019-10-07 17:07:41,338 32020 [INFO ] -
2019-10-07 17:07:41,357 32020 [ERROR] - Failures
2019-10-07 17:07:41,361 32020 [ERROR] - - git (exited 1) - git not installed. An error occurred during installation:
문자열의 길이는 0일 수 없습니다.
매개 변수 이름: variable
2019-10-07 17:07:41,375 32020 [DEBUG] - Sending message 'PostRunMessage' out if there are subscribers...
2019-10-07 17:07:41,468 32020 [DEBUG] - Exiting with 1
~~~