Naming a Reciever using accentuated letters and using a Screen supporting a Machine Information Module is definitely not a good idea.
*IMPORTANT NOTE : * this has only been tested on a multiplayer server using the FTB Infinity Modpack with FastCraft enabled.

My computer
Note that my friend with a different computer got the same errors as mine, but I give this info as it could be useful.
MSI gaming portable PC, running Windows 10 x64
Intel Core i7-4710HQ CPU @ 2.50 GHz
8.00 Go RAM
Java 8 update 74 (build 1.8.0_74-b02)

How to reproduce

1. Place a Matter Transmitter (it does not need any energy)
2. Place a Matter Reciever (nor does this one), and name it using an accentated character (I used "Ferme à bois", which is French for "Tree Farm")
3. Place a Screen Controller nearby the screen, power it and click Scan to power the Screen.
4. Dial the Matter Transmitter to the Matter Reciever using the method of your choice (Dialer, Simple Dialer...)
5. Obtain a Machine Information Module by any means (crafting, creative and commands will work) and shift-right click with it on the Matter Transmitter to link them
6. Place the Machine Information Module in the powered Screen, open the module's config, then choose to display the name.
7. If it states "<invalid>", this should work.
8. If the client doesn't crash, try loading the chunks (logging into the server or going far away then back do work), and the client should stop with a message like "A fatal error occured, this connection is terminated."

Console Output
The following error output spawned in the FTB Console every time the "fatal error" message terminated the connection.
[17:42:19] [Client thread/ERROR] [FML]: FMLIndexedMessageCodec exception caught io.netty.handler.codec.DecoderException: java.lang.ArrayIndexOutOfBoundsException: 15 at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:99) ~[MessageToMessageDecoder.class:?] at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111) ~[MessageToMessageCodec.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) [DefaultChannelPipeline.class:?] at io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:169) [EmbeddedChannel.class:?] at cpw.mods.fml.common.network.internal.FMLProxyPacket.func_148833_a(FMLProxyPacket.java:77) [FMLProxyPacket.class:?] at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212) [ej.class:?] at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273) [bje.class:?] at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1602) [bao.class:?] at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:973) [bao.class:?] at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:898) [bao.class:?] at net.minecraft.client.main.Main.main(SourceFile:148) [Main.class:?] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_74] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74] at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_74] at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?] at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?] Caused by: java.lang.ArrayIndexOutOfBoundsException: 15 at mcjty.rftools.blocks.screens.network.PacketReturnScreenData.fromBytes(PacketReturnScreenData.java:29) ~[PacketReturnScreenData.class:?] at cpw.mods.fml.common.network.simpleimpl.SimpleIndexedCodec.decodeInto(SimpleIndexedCodec.java:17) ~[SimpleIndexedCodec.class:?] at cpw.mods.fml.common.network.simpleimpl.SimpleIndexedCodec.decodeInto(SimpleIndexedCodec.java:7) ~[SimpleIndexedCodec.class:?] at cpw.mods.fml.common.network.FMLIndexedMessageToMessageCodec.decode(FMLIndexedMessageToMessageCodec.java:77) ~[FMLIndexedMessageToMessageCodec.class:?] at cpw.mods.fml.common.network.FMLIndexedMessageToMessageCodec.decode(FMLIndexedMessageToMessageCodec.java:17) ~[FMLIndexedMessageToMessageCodec.class:?] at io.netty.handler.codec.MessageToMessageCodec$2.decode(MessageToMessageCodec.java:81) ~[MessageToMessageCodec$2.class:?] at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:89) ~[MessageToMessageDecoder.class:?] ... 18 more

Then the following error, repeated 25 times (+/- one, I may have missed one)
[17:42:19] [Client thread/ERROR] [FML]: SimpleChannelHandlerWrapper exception io.netty.handler.codec.DecoderException: java.lang.ArrayIndexOutOfBoundsException: 15 at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:99) ~[MessageToMessageDecoder.class:?] at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111) ~[MessageToMessageCodec.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) [DefaultChannelPipeline.class:?] at io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:169) [EmbeddedChannel.class:?] at cpw.mods.fml.common.network.internal.FMLProxyPacket.func_148833_a(FMLProxyPacket.java:77) [FMLProxyPacket.class:?] at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212) [ej.class:?] at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273) [bje.class:?] at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1602) [bao.class:?] at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:973) [bao.class:?] at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:898) [bao.class:?] at net.minecraft.client.main.Main.main(SourceFile:148) [Main.class:?] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_74] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74] at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_74] at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?] at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?] Caused by: java.lang.ArrayIndexOutOfBoundsException: 15 at mcjty.rftools.blocks.screens.network.PacketReturnScreenData.fromBytes(PacketReturnScreenData.java:29) ~[PacketReturnScreenData.class:?] at cpw.mods.fml.common.network.simpleimpl.SimpleIndexedCodec.decodeInto(SimpleIndexedCodec.java:17) ~[SimpleIndexedCodec.class:?] at cpw.mods.fml.common.network.simpleimpl.SimpleIndexedCodec.decodeInto(SimpleIndexedCodec.java:7) ~[SimpleIndexedCodec.class:?] at cpw.mods.fml.common.network.FMLIndexedMessageToMessageCodec.decode(FMLIndexedMessageToMessageCodec.java:77) ~[FMLIndexedMessageToMessageCodec.class:?] at cpw.mods.fml.common.network.FMLIndexedMessageToMessageCodec.decode(FMLIndexedMessageToMessageCodec.java:17) ~[FMLIndexedMessageToMessageCodec.class:?] at io.netty.handler.codec.MessageToMessageCodec$2.decode(MessageToMessageCodec.java:81) ~[MessageToMessageCodec$2.class:?] at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:89) ~[MessageToMessageDecoder.class:?] ... 18 more

Last, the following error :
[17:42:19] [Client thread/ERROR] [FML]: There was a critical exception handling a packet on channel rftools io.netty.handler.codec.DecoderException: java.lang.ArrayIndexOutOfBoundsException: 15 at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:99) ~[MessageToMessageDecoder.class:?] at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111) ~[MessageToMessageCodec.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) ~[DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) ~[DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) ~[DefaultChannelPipeline.class:?] at io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:169) ~[EmbeddedChannel.class:?] at cpw.mods.fml.common.network.internal.FMLProxyPacket.func_148833_a(FMLProxyPacket.java:77) [FMLProxyPacket.class:?] at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212) [ej.class:?] at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273) [bje.class:?] at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1602) [bao.class:?] at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:973) [bao.class:?] at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:898) [bao.class:?] at net.minecraft.client.main.Main.main(SourceFile:148) [Main.class:?] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_74] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74] at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_74] at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?] at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?] Caused by: java.lang.ArrayIndexOutOfBoundsException: 15 at mcjty.rftools.blocks.screens.network.PacketReturnScreenData.fromBytes(PacketReturnScreenData.java:29) ~[PacketReturnScreenData.class:?] at cpw.mods.fml.common.network.simpleimpl.SimpleIndexedCodec.decodeInto(SimpleIndexedCodec.java:17) ~[SimpleIndexedCodec.class:?] at cpw.mods.fml.common.network.simpleimpl.SimpleIndexedCodec.decodeInto(SimpleIndexedCodec.java:7) ~[SimpleIndexedCodec.class:?] at cpw.mods.fml.common.network.FMLIndexedMessageToMessageCodec.decode(FMLIndexedMessageToMessageCodec.java:77) ~[FMLIndexedMessageToMessageCodec.class:?] at cpw.mods.fml.common.network.FMLIndexedMessageToMessageCodec.decode(FMLIndexedMessageToMessageCodec.java:17) ~[FMLIndexedMessageToMessageCodec.class:?] at io.netty.handler.codec.MessageToMessageCodec$2.decode(MessageToMessageCodec.java:81) ~[MessageToMessageCodec$2.class:?] at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:89) ~[MessageToMessageDecoder.class:?] ... 18 more

Then the usual deconnection messages (netty restoring client configs, etc.)

Final note
My best guess on this one comes from this :
Caused by: java.lang.ArrayIndexOutOfBoundsException: 15 at mcjty.rftools.blocks.screens.network.PacketReturnScreenData.fromBytes(PacketReturnScreenData.java:29) ~[PacketReturnScreenData.class:?]
As I used an accentuated character, my best guess is that the code that turns the byte stream into characters uses an array, which does not accomodate accentuated characters.

Also, simply using /setblock to delete the faulty screen allowed the chunk the screen was in to be safely loaded again.

What version of rftools?

The provided by the latest version of FTB Infinity, that is... 4.22

Close as 1.7.10 is no longer supported. If this continues to be a bug on 1.12 or newer, please open a new issue.