diff --git a/src/main/claude-accounts/claude-account-selection.ts b/src/main/claude-accounts/claude-account-selection.ts
index 22234b1fdde..6f9523402ec 100644
--- a/src/main/claude-accounts/claude-account-selection.ts
+++ b/src/main/claude-accounts/claude-account-selection.ts
@@ -10,6 +10,7 @@ import { savedWslClaudeAccountHome } from './claude-profile-wsl-paths'
 import type { ClaudeRuntimeAuthService } from './runtime-auth-service'
 import {
   getClaudeSelectionTargetForAccount,
+  getClaudeWslSelectionKey,
   getSelectedClaudeAccountIdForTarget,
   normalizeClaudeAccountSelectionTarget,
   normalizeClaudeRuntimeSelection,
@@ -179,7 +180,9 @@ export class ClaudeAccountSelection {
       const owned = normalizeClaudeAccountSelectionTarget(accountTarget)
       if (
         requested.runtime !== owned.runtime ||
-        (requested.wslDistro !== null && requested.wslDistro !== owned.wslDistro)
+        (requested.wslDistro !== null &&
+          getClaudeWslSelectionKey(requested.wslDistro) !==
+            getClaudeWslSelectionKey(owned.wslDistro))
       ) {
         throw new Error('That Claude account belongs to a different runtime.')
       }
diff --git a/src/main/claude-accounts/claude-account-service.test.ts b/src/main/claude-accounts/claude-account-service.test.ts
index 2baf96adf9a..72ab9844a50 100644
--- a/src/main/claude-accounts/claude-account-service.test.ts
+++ b/src/main/claude-accounts/claude-account-service.test.ts
@@ -544,4 +544,32 @@ describe('ClaudeAccountService', () => {
       'That Claude account belongs to a different runtime.'
     )
   })
+
+  it('selects and clears a WSL account across casing while retaining its recorded distro', async () => {
+    const f = fixture([
+      account('a'),
+      account('w', {
+        managedAuthRuntime: 'wsl',
+        wslDistro: 'Ubuntu',
+        wslLinuxAuthPath: '/home/u/.local/share/orca/claude-profiles/w/home'
+      })
+    ])
+    const selected = await f.service.selectAccountForTarget('w', {
+      runtime: 'wsl',
+      wslDistro: 'ubuntu'
+    })
+    expect(selected.activeAccountIdsByRuntime).toEqual({ host: 'a', wsl: { Ubuntu: 'w' } })
+    expect(f.runtimeAuth.syncForCurrentSelection).toHaveBeenCalledWith({
+      runtime: 'wsl',
+      wslDistro: 'Ubuntu'
+    })
+    await expect(
+      f.service.selectAccountForTarget('w', { runtime: 'wsl', wslDistro: 'Debian' })
+    ).rejects.toThrow('different runtime')
+    const cleared = await f.service.selectAccountForTarget(null, {
+      runtime: 'wsl',
+      wslDistro: 'ubuntu'
+    })
+    expect(cleared.activeAccountIdsByRuntime).toEqual({ host: 'a', wsl: { Ubuntu: null } })
+  })
 })
diff --git a/src/main/claude-accounts/claude-profile-paths.test.ts b/src/main/claude-accounts/claude-profile-paths.test.ts
index e489c4a8434..1e116c7b368 100644
--- a/src/main/claude-accounts/claude-profile-paths.test.ts
+++ b/src/main/claude-accounts/claude-profile-paths.test.ts
@@ -43,6 +43,44 @@ afterEach(() => {
 const local = { runtime: 'host', executionHostId: 'local' } as const
 
 describe('Claude profile namespace', () => {
+  it.skipIf(process.platform === 'win32')(
+    'accepts a WSL casing alias while retaining the original marker and rejecting other owners',
+    () => {
+      const dir = root()
+      const userHome = root()
+      const profile = describeClaudeProfile(dir, 'a', {
+        ...local,
+        runtime: 'wsl',
+        distro: 'Ubuntu'
+      })
+      prepareClaudeProfileDirectory(dir, profile, userHome)()
+      const marker = join(dir, 'claude-profiles/a/profile.json')
+      const original = readFileSync(marker, 'utf8')
+      prepareClaudeProfileDirectory(
+        dir,
+        { ...profile, target: { ...profile.target, runtime: 'wsl', distro: 'ubuntu' } },
+        userHome
+      )()
+      expect(readFileSync(marker, 'utf8')).toBe(original)
+      for (const distro of ['Debian', 'Ubuntu-24.04']) {
+        expect(() =>
+          prepareClaudeProfileDirectory(
+            dir,
+            { ...profile, target: { ...local, runtime: 'wsl', distro } },
+            userHome
+          )
+        ).toThrow('another account or target')
+      }
+      writeFileSync(
+        marker,
+        JSON.stringify({ version: 1, accountId: 'b', runtime: 'wsl', distro: 'ubuntu' })
+      )
+      expect(() => prepareClaudeProfileDirectory(dir, profile, userHome)).toThrow(
+        'another account or target'
+      )
+    }
+  )
+
   // A WSL profile's data root is a POSIX path; a Windows temp dir cannot be one.
   it.skipIf(process.platform === 'win32')(
     'binds the new namespace to an account and execution target without touching legacy auth',
diff --git a/src/main/claude-accounts/claude-profile-paths.ts b/src/main/claude-accounts/claude-profile-paths.ts
index 3c61c1c901d..62471150aa1 100644
--- a/src/main/claude-accounts/claude-profile-paths.ts
+++ b/src/main/claude-accounts/claude-profile-paths.ts
@@ -78,6 +78,20 @@ function ownershipRecord(
   return JSON.stringify({ version, accountId, runtime, distro })
 }
 
+function comparableOwnershipRecord(
+  version: unknown,
+  accountId: unknown,
+  runtime: unknown,
+  distro: unknown
+): string {
+  return ownershipRecord(
+    version,
+    accountId,
+    runtime,
+    runtime === 'wsl' && typeof distro === 'string' ? distro.trim().toLowerCase() : distro
+  )
+}
+
 function readOwnershipMarker(file: string): string | null {
   try {
     if (!lstatSync(file).isFile()) {
@@ -94,7 +108,7 @@ function readOwnershipMarker(file: string): string | null {
     throw new ClaudeProfileSurfaceError('unreadable', 'Claude profile marker is unreadable')
   }
   const { version, accountId, runtime, distro } = marker.value
-  return ownershipRecord(version, accountId, runtime, distro)
+  return comparableOwnershipRecord(version, accountId, runtime, distro)
 }
 
 // Written when a first setup finishes, so its absence means no setup has finished here yet.
@@ -132,7 +146,11 @@ export function prepareClaudeProfileDirectory(
   const distro = profile.target.runtime === 'wsl' ? profile.target.distro : undefined
   const record = ownershipRecord(profile.version, profile.accountId, profile.target.runtime, distro)
   const marker = readOwnershipMarker(markerPath)
-  if (marker !== null && marker !== record) {
+  if (
+    marker !== null &&
+    marker !==
+      comparableOwnershipRecord(profile.version, profile.accountId, profile.target.runtime, distro)
+  ) {
     throw new ClaudeProfileSurfaceError(
       'invalid-profile',
       'Claude profile belongs to another account or target'
diff --git a/src/main/claude-accounts/claude-profile-wsl-router.test.ts b/src/main/claude-accounts/claude-profile-wsl-router.test.ts
index 3da53b6a4dc..f6ba3b2b15e 100644
--- a/src/main/claude-accounts/claude-profile-wsl-router.test.ts
+++ b/src/main/claude-accounts/claude-profile-wsl-router.test.ts
@@ -96,6 +96,20 @@ function fixture() {
 }
 
 describe.skipIf(!posixHost)('ClaudeWslProfileRouter', () => {
+  it('publishes and launches the saved account across distro casing without changing guest spelling', async () => {
+    const f = fixture()
+    await f.router.publish('ubuntu')
+    expect(readFileSync(f.pointer, 'utf8')).toBe(f.profileHome)
+    const launch = await f.router.prepareLaunch('ubuntu')
+    expect(launch).toMatchObject({
+      wslDistro: 'ubuntu',
+      envPatch: { CLAUDE_CONFIG_DIR: f.profileHome }
+    })
+    f.settings.claudeManagedAccounts[0].wslDistro = 'ubuntu'
+    expect(await f.router.runningDistros()).toEqual(['Ubuntu'])
+    expect((await f.router.preparation('Ubuntu')).envPatch.CLAUDE_CONFIG_DIR).toBe(f.profileHome)
+  })
+
   it('writes the guest pointer per build, sets up even a missing folder, and removes it with the last account', async () => {
     const f = fixture()
     await f.router.publish('Ubuntu')
@@ -362,13 +376,17 @@ it.skipIf(!posixHost)(
       external: ['electron'],
       logLevel: 'silent'
     })
-    const run = (accountId: string) =>
-      spawnSync(process.execPath, [helper, home, 'Ubuntu', accountId], { encoding: 'utf8' })
+    const run = (accountId: string, distro = 'Ubuntu') =>
+      spawnSync(process.execPath, [helper, home, distro, accountId], { encoding: 'utf8' })
 
     expect(run('a').status).toBe(0)
     expect(existsSync(join(profileHome, '..', 'profile.json'))).toBe(true)
     // History is a Linux link into the guest's own ~/.claude.
     expect(lstatSync(join(profileHome, 'projects')).isSymbolicLink()).toBe(true)
+    const marker = readFileSync(join(profileHome, '..', 'profile.json'), 'utf8')
+    expect(run('a', 'ubuntu').status).toBe(0)
+    expect(readFileSync(join(profileHome, '..', 'profile.json'), 'utf8')).toBe(marker)
+    expect(run('a', 'Debian').status).not.toBe(0)
     expect(run('../escape').status).not.toBe(0)
   }
 )
diff --git a/src/main/claude-accounts/runtime-selection.test.ts b/src/main/claude-accounts/runtime-selection.test.ts
index b7f64aede99..902d175761f 100644
--- a/src/main/claude-accounts/runtime-selection.test.ts
+++ b/src/main/claude-accounts/runtime-selection.test.ts
@@ -41,6 +41,67 @@ function createAccount(
 }
 
 describe('Claude runtime account selection', () => {
+  it('reads legacy distro spelling without changing the selection or launch target', () => {
+    const settings = createSettings({
+      activeClaudeManagedAccountIdsByRuntime: {
+        host: 'host-account',
+        wsl: { Ubuntu: 'wsl-account', Debian: 'debian-account' }
+      }
+    })
+    for (const wslDistro of ['Ubuntu', 'ubuntu', ' UBUNTU ']) {
+      expect(getSelectedClaudeAccountIdForTarget(settings, { runtime: 'wsl', wslDistro })).toBe(
+        'wsl-account'
+      )
+    }
+    expect(
+      getSelectedClaudeAccountIdForTarget(settings, { runtime: 'wsl', wslDistro: 'Fedora' })
+    ).toBeNull()
+    expect(settings.activeClaudeManagedAccountIdsByRuntime?.wsl).toEqual({
+      Ubuntu: 'wsl-account',
+      Debian: 'debian-account'
+    })
+  })
+
+  it('updates every saved alias while preserving their spelling and unrelated runtimes', () => {
+    const selection = { host: 'host-account', wsl: { Ubuntu: 'a', ubuntu: 'a', Debian: 'd' } }
+    const changed = setSelectedClaudeAccountIdForTarget(selection, 'b', {
+      runtime: 'wsl',
+      wslDistro: 'UBUNTU'
+    })
+    expect(changed).toEqual({
+      host: 'host-account',
+      wsl: { Ubuntu: 'b', ubuntu: 'b', Debian: 'd' }
+    })
+    expect(
+      setSelectedClaudeAccountIdForTarget(changed, null, { runtime: 'wsl', wslDistro: 'ubuntu' })
+    ).toEqual({ host: 'host-account', wsl: { Ubuntu: null, ubuntu: null, Debian: 'd' } })
+    expect(selection.wsl.Ubuntu).toBe('a')
+  })
+
+  it('keeps exact legacy spellings and does not choose between conflicting aliases', () => {
+    for (const wsl of [
+      { Ubuntu: 'a', ubuntu: 'b' },
+      { Ubuntu: 'a', ubuntu: null }
+    ]) {
+      const settings = createSettings({
+        activeClaudeManagedAccountIdsByRuntime: { host: null, wsl }
+      })
+      const lookup = (wslDistro: string) =>
+        getSelectedClaudeAccountIdForTarget(settings, { runtime: 'wsl', wslDistro })
+      expect(lookup('Ubuntu')).toBe('a')
+      expect(lookup('ubuntu')).toBe(wsl.ubuntu)
+      expect(lookup('UBUNTU')).toBeNull()
+    }
+  })
+
+  it('retains selections when account and legacy map distro casing differ', () => {
+    expect(
+      pruneInvalidClaudeRuntimeSelection({ host: null, wsl: { ubuntu: 'a', Debian: 'a' } }, [
+        createAccount({ id: 'a', managedAuthRuntime: 'wsl', wslDistro: 'Ubuntu' })
+      ])
+    ).toEqual({ host: null, wsl: { ubuntu: 'a', Debian: null } })
+  })
+
   it('selects host and WSL accounts independently', () => {
     const first = setSelectedClaudeAccountIdForTarget({ host: null, wsl: {} }, 'host-account', {
       runtime: 'host'
diff --git a/src/main/claude-accounts/runtime-selection.ts b/src/main/claude-accounts/runtime-selection.ts
index 1fc5137bb17..e9cfe2e754d 100644
--- a/src/main/claude-accounts/runtime-selection.ts
+++ b/src/main/claude-accounts/runtime-selection.ts
@@ -52,7 +52,13 @@ export function getSelectedClaudeAccountIdForTarget(
     return selection.host
   }
   if (normalizedTarget.wslDistro) {
-    return selection.wsl[getClaudeWslSelectionKey(normalizedTarget.wslDistro)] ?? null
+    // Why exact first: a saved spelling that matches keeps resolving as it did before aliasing.
+    if (Object.hasOwn(selection.wsl, normalizedTarget.wslDistro)) {
+      return selection.wsl[normalizedTarget.wslDistro] ?? null
+    }
+    const matches = matchingWslSelectionKeys(selection.wsl, normalizedTarget.wslDistro)
+    const ids = new Set(matches.map((key) => selection.wsl[key]))
+    return ids.size === 1 ? (ids.values().next().value ?? null) : null
   }
   const selectedIds = Array.from(new Set(Object.values(selection.wsl).filter(Boolean)))
   return (
@@ -76,12 +82,15 @@ export function setSelectedClaudeAccountIdForTarget(
       wsl: Object.fromEntries(Object.keys(selection.wsl).map((key) => [key, null]))
     }
   }
+  const wsl = { ...selection.wsl }
+  const matches = matchingWslSelectionKeys(wsl, normalizedTarget.wslDistro)
+  // Retain saved spelling for older clients; an explicit switch reconciles existing aliases.
+  for (const key of matches.length > 0 ? matches : [normalizedTarget.wslDistro ?? '__default__']) {
+    wsl[key] = accountId
+  }
   return {
     host: selection.host,
-    wsl: {
-      ...selection.wsl,
-      [getClaudeWslSelectionKey(normalizedTarget.wslDistro)]: accountId
-    }
+    wsl
   }
 }
 
@@ -116,7 +125,7 @@ export function pruneInvalidClaudeRuntimeSelection(
     nextWsl[distroKey] =
       account &&
       account.managedAuthRuntime === 'wsl' &&
-      getClaudeWslSelectionKey(account.wslDistro) === distroKey
+      getClaudeWslSelectionKey(account.wslDistro) === getClaudeWslSelectionKey(distroKey)
         ? accountId
         : null
   }
@@ -136,7 +145,15 @@ export function getClaudeSelectionTargetForAccount(
 }
 
 export function getClaudeWslSelectionKey(wslDistro: string | null | undefined): string {
-  return normalizeWslDistro(wslDistro) ?? '__default__'
+  return normalizeWslDistro(wslDistro)?.toLowerCase() ?? '__default__'
+}
+
+function matchingWslSelectionKeys(
+  selection: Record<string, string | null>,
+  distro: string | null
+): string[] {
+  const key = getClaudeWslSelectionKey(distro)
+  return Object.keys(selection).filter((saved) => getClaudeWslSelectionKey(saved) === key)
 }
 
 function normalizeWslDistro(wslDistro: string | null | undefined): string | null {