Fix TBSIMP_E_BUFFER_TOO_SMALL (0X80290200) in 3 Steps

What’s this error? And when does it show up?

You’ll see 0X80290200 with the message “The specified buffer was too small” when you try to install a Windows update, run a BitLocker action, or use any app that talks to the TPM chip. I’ve seen it most often on Dell and Lenovo laptops running Windows 10 21H2 or 11 22H2. The TPM (Trusted Platform Module) is what handles encryption keys, and sometimes the buffer it allocates for data exchange just isn’t big enough. The OS throws this error and stops whatever you were doing.

Don’t panic. Nine times out of ten, the fix is simple — clear the TPM and restart. But I’ll give you three options, from quickest to most thorough. Try them in order. Stop when the error goes away.

Before you start: make sure you’re logged in as an administrator. You’ll need that for all three fixes.

Fix 1: The 30-second fix — Clear the TPM

This is the fastest way. Clearing the TPM resets its internal state, including any temporary buffers that got stuck. You won’t lose your BitLocker keys if you have the recovery key saved — and you should have that saved anyway.

Press Windows + R to open the Run dialog.
Type tpm.msc and hit Enter. The TPM Management console opens.
On the right side, click Clear TPM. You’ll see a warning — read it, then click Restart.
Your PC restarts. During boot, you’ll get a screen asking to press F12 (or F2 on some machines) to confirm. Do that.
Windows boots normally. The TPM is now reset.

Expected outcome after restart: The error should be gone. Try your update or app again. If it still shows up, move to Fix 2.

Trust me on this: 80% of users stop here. Don’t waste time if you’re not having success — just do this and test.

Fix 2: The 5-minute fix — Update the TPM driver

If clearing the TPM didn’t help, the driver might be old or corrupt. Windows Update sometimes pushes a generic driver that doesn’t match your hardware. You need the one from your PC manufacturer.

Press Windows + X and select Device Manager.
Expand Security devices. You should see Trusted Platform Module 2.0 (or 1.2 on older machines). If you see a yellow exclamation mark, that’s your cue.
Right-click the TPM entry and select Update driver.
Click Browse my computer for drivers.
Click Let me pick from a list of available drivers on my computer.
In the list, choose the driver that matches your manufacturer (e.g., “Intel TPM 2.0” or “AMD TPM 2.0”). If you see multiple, pick the one from your PC maker — Dell, Lenovo, HP — not Microsoft.
Click Next and wait for the installation to finish.

After you click Next: You might get a “Windows has successfully updated your driver” message. If you don’t see that, the driver didn’t change. In that case, go to your PC manufacturer’s support site, download the latest TPM driver for your exact model, and install it manually.

Restart your PC after the driver update. Then test your update or app.

One thing I see a lot: People install a generic driver from the Windows Update catalog. That often makes the problem worse. Stick with the manufacturer driver. It’s tested for your hardware.

Fix 3: The advanced fix (15+ minutes) — Repair Windows Update components and check TPM firmware

If you’re still seeing 0X80290200, the issue might be deeper — corrupted Windows Update files or outdated TPM firmware. You’ll need to run a few commands and maybe update the firmware.

Step 3a: Reset Windows Update components

Open an admin Command Prompt. Search for cmd, right-click it, and select Run as administrator.
Stop the Windows Update service, the BITS service, and the Cryptographic services by running these commands one at a time. Press Enter after each:
```
net stop wuauserv
net stop bits
net stop cryptsvc
```
Expected output: Each command should say “The service was stopped successfully.”
Delete the old update cache. Run:
```
del /f /s /q %windir%\SoftwareDistribution\*.*
rd /s /q %windir%\SoftwareDistribution
```
Expected outcome: You might see errors if files are in use — ignore them, because the next reboot will clean them up.
Restart the services you stopped:
```
net start wuauserv
net start bits
net start cryptsvc
```
After the last command: You should see “The service started successfully” for each.
Type exit and close the Command Prompt.

Restart your PC. Try your update or app again.

Step 3b: Update TPM firmware (if the error persists)

This is rare, but I’ve seen it on older Intel NUCs and some HP ProBooks. TPM firmware updates are delivered through your PC maker’s tool or BIOS update.

Go to your manufacturer’s support page. Search for your exact model number (you’ll find it on the bottom sticker or in System Information).
Look for a “BIOS/Driver” download section. Check for “TPM Firmware Update” or “Firmware Update for TPM 2.0”.
Download and run the installer. Most of these are self-extracting executables that update during boot.
Follow the on-screen prompts. Your PC will restart at least once.

Important: Do not interrupt the update process. If you lose power mid-update, you can brick the TPM and need a motherboard replacement. Plug into a wall outlet if you’re on a laptop.

After the firmware update, reboot again. The 0X80290200 error should be gone.

When to give up and call support

If none of these fixes work, there’s a chance your TPM hardware is failing. You’ll see the error even after a clean Windows install. In that case, contact your PC manufacturer or check if your motherboard is under warranty. Some Dell and HP models from 2018-2019 have known TPM issues that require a hardware replacement.

But honestly — try Fix 1 first. Most people never get past that.