If you have spent any amount of time trading with a prop firm, you know at least one thing for sure: execution matters. Every second counts. Every hiccup is a nuisance. Every technical problem seems like the universe is out to get your funded account. While MT5 is a good, stable platform, it is not immune to the occasional freeze, lag, failure of a login, or a random crash just when you wanted to move the stop-loss.
Don’t worry-you’re definitely not alone. Every trader who has spent more than a week on MT5 has, at one point or another, run into something frustrating. Fortunately, most issues are surprisingly easy to fix once you know where to look.
So, let’s break down the most common MT5 problems prop traders run into and walk through some practical, real-world troubleshooting steps you can use to get everything back on track in no time.
Login Errors: When MT5 Says “No” to Your Account
There’s nothing as frustrating as attempting to jump into the market, especially during high-volatility sessions, only for MetaTrader 5 to throw a login error at you.
The suspects usually include:
Improper selection of server
This is, by far, the most frequent mistake, particularly for traders in multi-phase prop firm challenges: Prop firms usually provide:
- A demo/challenge server
- A verification server
- A funded/live server
- and the names are very similar.
Solution: Double-check the exact server name your prop firm sent you. Even a small difference, such as “Live01” vs “Live1”, will prevent login.
Incorrect password
If you’ve changed your investor or master password recently, it may be that MT5 is still trying to use the old one.
Manually input the password, rather than relying on auto-fill.
Account disabled or expired
Prop firm challenges mostly expire after a certain number of days. Some firms auto-disable the account if you hit your daily or max drawdown.
- Check your e-mail or the trader’s dashboard for confirmation of the account status.
Blocked by firewall or antivirus
Some security software blocks MT5’s port communication.
To fix this, include MT5 in the exceptions list in your firewall or antivirus software.
Restart MT5 afterwards.
MT5 Freezing or Lagging: The Classic “Not Responding” Nightmare
When MT5 becomes slow, freezes in the middle of a trade, or takes ages to load charts, it is not only frustrating but also costly.
Here’s what usually causes lag:
Too many open charts
Some traders open every timeframe under the sun. MT5 can handle a lot, but not that much.
Close charts that you are not actively using.
Remove unused indicators.
Restart the platform to refresh memory usage.
Heavy custom indicators or EAs
The best prop firm traders love stacking indicators. But poorly coded ones can drain your RAM in no time.
Correct:
Remove indicators one by one until the culprit is found.
Try substituting with lightweight alternatives.
If an EA is problematic, always check the Journal tab to see if it’s spamming any errors.
Poor internet connectivity
Even a short loss in connectivity could freeze charts or delay orders.
Correct:
Run a speed test.
If possible, use Ethernet instead of Wi-Fi.
Connect to a VPS if you are a news trader or scalper.
old or corrupted cache data
MT5 stores loads of temporary data; that can really slow down everything over time.
Fix:
Go to File → Open Data Folder → Bases
Delete old server folders (do not worry MT5 will rebuild them).
Restart MT5.
Charts Not Updating: When Price Just… Stops Moving
If your chart appears to freeze without MT5 closing, don’t freak out. Often this occurs due to:
Your account is disconnected
Check the bottom right corner of the platform; if it’s red or showing “0/0 kb, you’re offline.
You’re on the wrong symbol or feed
Some prop firms provide synthetic or custom data feeds.
Corrections:
Right-click Market Watch → Show All
Choose the exact symbol your prop firm lists; for example, “XAUUSD.a” vs “XAUUSD”.
Market is closed
It sounds obvious, but it happens—especially with indices, CFDs, and metals which close earlier on Fridays.
Corrupted chart data
Sometimes the feed just glitches.
Correct:
Right-click the chart → Refresh
If still stuck:
Delete the symbol’s history folder, in the data directory.
Orders Not Executing: The most stressful issue for Prop Traders
There’s nothing like clicking “Buy” during NFP and nothing happens.
If orders fail, MT5 will usually show a message like:
- “Trade is disabled”
- “Off quotes”
- “Invalid price”
- “No connection”
- “Market closed”
Here are the causes and fixes:
Trade disabled on account
Some firms auto-disable trading if you hit drawdown, or if trading hours are restricted.
Trading outside allowed hours
Prop firms often block trading on specific assets during rollover or low-liquidity times.
Check the symbol’s contract specifications.
Off quotes / invalid prices
This happens during high volatility, or news spikes.
Correct:
Try market execution instead of instant execution.
Expand your slippage settings, if possible.
Slow internet or high ping
Ping more than 80–100 ms can delay orders.
Improvements:
Use a VPS that is close to the prop firm’s server.
Close bandwidth-heavy applications.
Stop levels too tight
Some brokers require a minimum distance between price and your stop-loss/take-profit.
Correctness:
Check symbol specs → “Stop level”
Adjust SL/TP accordingly.
Indicators Not Showing or Not Working
If you have ever installed any custom indicator and it disappears like a ghost, then don’t blame MT5 just yet.
Wrong installation folder
MT5 has separate folders for indicators, scripts, and EAs.
Repairs:
Place .ex5 files in:
MQL5 → Indicators
Restart MT5.
Compiled with errors
The indicator will not display if it was not compiled correctly in MetaEditor.
Correct: Open MetaEditor → compile → look for red error messages.
Using MT4 indicators in MT5
They are not compatible, since they have different file formats.