Zwischenablage Diagnose

This article helps you diagnose clipboard issues in Remote Desktop Manager; copies that fail to paste, values that disappear too quickly, or applications that behave inconsistently between browsers.

Use this list to go directly to the section that matches your symptom. If multiple symptoms seem to apply, start with the first one that matches.

• Paste into a browser does nothing (but works in another browser). See Null requester check.

• Paste works once, then stops. See Paste Once and delays.

• The clipboard clears itself after a few seconds. See Clear clipboard delay.

• A specific application keeps reading the clipboard. See Blocklist management.

• The clipboard appears blank immediately after copy. See How to read the profiler.

Before changing any settings, confirm where the problem is by running this fast test:

1. In Remote Desktop Manager, copy a credential (or any entry value) to the clipboard.

2. Open Notepad and press Ctrl+V.

   • If the value pastes correctly, Remote Desktop Manager is copying fine. The problem is with the target application's clipboard read.

   • If nothing pastes, Remote Desktop Manager is not publishing the value. Continue with How to read the profiler.

3. Open the target application (for example Chrome) and press Ctrl+V in a text field.

   • If it works, no further action is needed.

   • If nothing pastes, you most likely hit the Null requester check.

4. Optional: repeat step 3 in a second browser (for example Microsoft Edge). If it works in one browser but not the other, this confirms the null requester check is the cause.

Remote Desktop Manager refuses to hand clipboard data to any process that does not identify itself with a visible window. This protects your credentials from invisible or background processes that try to read the clipboard silently.

In the clipboard profiler, a blocked request appears as:

Clipboard - Render - Requester : 0 - Format : 13

Requester : 0 means the requesting process did not provide a window handle.

• Recent versions of Google Chrome (clipboard reads issued from a background renderer thread).

• Some Electron-based applications.

• Certain clipboard manager and automation tools.

Microsoft Edge and most native Windows applications are not affected; they request the clipboard with a proper window handle.

1. Go to File – Options – Advanced – Clipboard.

2. Enable Disable clipboard null requester check.

3. Click OK and retry the copy and paste.

Instead of disabling the check, choose one of the following:

• Paste into Microsoft Edge or another browser that uses a visible window handle.

• Use the separate Copy username and Copy password actions from the entry's context menu and paste immediately.

• Paste into a native field (for example Notepad) first, then copy from there into the target application.

The clipboard profiler logs every step of a copy and paste cycle. The table below maps the most common lines to their meaning and the recommended action.

Format ID	Description
13	CF_UNICODETEXT — the pasted text itself.
49924, 49925, 49930, 50004, 50005	Represents private formats advertised by Remote Desktop Manager as definied by Microsoft and others. Clipboard Viewer Ignore CanIncludeInClipboardHistory CanUploadToCloudClipboard ExcludeClipboardContentFromMonitorProcessing RDMClipboardContent

Paste Once is a clipboard copy method that clears the clipboard after a configured number of paste operations, to prevent the credential from lingering in the clipboard history.

• The clipboard advertises the copied value to Windows.

• Each time a process reads the clipboard, the Paste Once counter decrements.

• When the counter reaches zero, Remote Desktop Manager clears the clipboard.

Some applications read the clipboard multiple times for a single paste to preview content, populate the paste menu, or sync with cloud clipboard services.

These background reads consume Paste Once counts before you actually paste.

Symptoms:

• The first paste works, but the value is cleared too quickly to paste a second time.

• The profiler shows multiple Render - Requester : <hwnd> lines before your explicit paste.

1. Go to File – Options – Advanced – Clipboard.

2. Do one of the following:

   • Increase the Paste Once count so background reads do not exhaust the allowance before your paste.

   • Switch Clipboard copy method to Legacy (the classic Windows clipboard, with no paste-once protection).

For some applications, a better option is to add a per-process delay so Remote Desktop Manager waits before publishing the value:

1. Open the Clipboard diagnostic window from the Help menu.

2. In the Configuration tab, add a delay entry for the target application.

3. A value between 150 ms and 500 ms works for most browsers.

Remote Desktop Manager can automatically clear the clipboard after a configurable number of seconds. This is separate from Paste Once because it is a time-based safety net, not a read-count one.

1. Go to File – Options – Advanced – Clipboard.

2. Enable Clear clipboard after and set the delay in seconds.

3. Click OK.

• The clipboard is full right after you copy, but empties on its own a few seconds later.

• The profiler shows a Clear line some seconds after the copy, without any Render - Requester : 0 or blocklist activity.

• 10–30 seconds: balanced, long enough for most paste workflows, short enough to limit exposure.

• Disabled: only if you use Paste Once or rely on an external clipboard manager for cleanup.

The Status tab of the clipboard diagnostic window lists every process that has requested the clipboard since Remote Desktop Manager started. Each entry shows the process name, PID, command line, and whether the process is currently allowlisted, blocklisted, or detected as an auto-reader.

1. Open the Clipboard diagnostic window from the Help menu.

2. In the Status tab, right-click the process you want to block.

3. Select Add to blocklist.

Blocklisted processes receive an empty clipboard when they request credentials from Remote Desktop Manager.

Use the allowlist for trusted applications that Remote Desktop Manager would otherwise block for example, because they trigger the null requester check or were flagged as auto-readers.

1. Open the Clipboard diagnostic window from the Help menu in the ribbon of Remote Desktop Manager.

2. In the Status tab, right-click the process you want to allow.

3. Select Add to allowlist.

1. In the Status tab, right-click the process.

2. Select Remove from blocklist or Remove from allowlist.

Some applications request the clipboard in a way that triggers the null requester check. The list below is maintained as issues are reported. If the application you use is not listed, follow the Test in 30 seconds flow to determine whether the null requester check is involved.

If none of the above resolves the issue, send a diagnostic report so the support team can review the profiler output:

1. Open the Clipboard diagnostic window from the Help menu in the ribbon of Remote Desktop Manager.

2. Reproduce the failing copy and paste so the profiler captures the event.

3. Click Send.

4. In the Send message to Devolutions support team window, include a short description of:

   • The source entry type (credential, web browser, etc.).

   • The target application and version (for example, Chrome 135).

   • Whether the same copy works in another application.

5. Click Send.

• Devolutions Academy - How to perform a clipboard diagnostic