I have a red vertical line on my dell inspiron laptop.How do I remove it?,please

Try connecting an external monitor to the Dell Inspiron 9300and see if the vertical line is also present on the monitor. If themonitor display is fine, then your laptop’s LCD display panel isdefective. If the monitor also displays the vertical line, then yourproblem is with either the video card or motherboard located insideyour laptop.
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Another answer:

run the PSA diagnostics. to do so, press and holdany non-keyboard button( like the internet hotkey or access directbutton or even the speaker mute button) and then press the power buttonand power up your system. if your inspiron doesn't have a non-kbbutton, then press the <fn> key.
release both the buttons and the diagnostics begin to run.after thediags finish. if the monitor is working fine, it'll simply say"passed". however, if it fails it would emit a few beep codes.carefully check those beep codes:
1.) if you get a 3-3-3 or a 3-3-4 error beeps, then we use the LCDbuilt in self-test (BIST). boot to PSA diagnostics again. Watch thescreen and listen for the color bar test prompt tones emitted by thePSA Diagnostics. Press <N> or wait approximately 30 seconds tofail the color bar test. The system will emit a 3-3-3 or 3-3-4 PSAerror after failing the color bar test. Wait for two iterations of thefailure code then press <Y>.
Watch for the BIST color generation and listen for the single beeps that indicate LCD BIST is running.
NOTE: Patterns of flashing color should appear on the screen. Withevery color change, an audible beep will be heard. If the patterns ofcolor do not appear, and the beeps are audible, an LCD failure may bethe issue. If the patterns of color appear, a video card or motherboardfailure may be the issue.

2.)if you get an error code apart from 3-3-3 or 3-3-4 :Ensure thesystem is powered off. Press and hold the <Fn> key and press thepower button to power the system on. Release both buttons.
The PSA diagnostics sequence begins. Make note of any alert tones or error messages.
error codes:
123- memory fails
141,142,143,144,145,146 hard drive error
147- IDE optical drive fails
148 optical drive built in test fails
122-memory test initialization test failure
111- fatal diagnostics exception.

i really hope you dont get any of these. these will help you determine,if you need to change the LCD. when you call dell, they will run youthrough these steps anyways. so if you finish them beforehand, you wontpay much to talk to them. cheerio then.
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