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[Solved] Need FSUIPC4 4.957b for Windows XP SP3 / FSX / PFC Cirrus II

Posts: 1

ckuelzow

Registered

Topic starter

September 6, 2026 9:59 pm

(@ckuelzow)

Joined: 1 month ago

I am restoring a legacy PFC Cirrus II simulator running Windows XP SP3 32-bit and Microsoft Flight Simulator X. I need an older XP-compatible copy of FSUIPC4 v4.957b, or another confirmed pre-4.96 version.

I understand current FSUIPC4 versions no longer support XP. If anyone has the original 4.957b installer/package from a legitimate archive and can share it, I would greatly appreciate it.

I am also looking for the compatible PFCFSX.dll for the serial PFC Cirrus II using COM1.

Thank you.

4 Replies

Posts: 402

FSUIPC Support

Moderator

September 7, 2026 9:50 am

(@fsuipc-support)

Joined: 12 months ago

Sorry but I do not have any older versions of FSUIPC4 available. You could try posting on avsim to see if anyone still using XP has this version.

The PFCX.dll is contained in the PFC DLL package available in the 'All Products' download page. I do not know if this is compatible with XP or not, sorry.

John

Posts: 1

Erdorfo

Registered

September 26, 2026 11:56 am

(@erdorfo)

Joined: 3 weeks ago

Hello,

I have FSUIPC4. Attached here.

Attachment : FSUIPC4 4.964.zip

Adolfo

Posts: 402

FSUIPC Support

Moderator

September 26, 2026 3:45 pm

(@fsuipc-support)

Joined: 12 months ago

The OP (@ckuelzow) is looking for a version before that (i.e. pre 4.96) for XP - or can you confirm that the version you attached (4.964) is compatible with XP?

Posts: 402

FSUIPC Support

Moderator

September 27, 2026 4:52 pm

(@fsuipc-support)

Joined: 12 months ago

@ckuelzow

Pete had a copy of 4957b - it is attached. However, this is the dll only, i.e. no installer. If you already have FSUIPC4 installed, just replace the FSUIPC4.dll with this one.

Otherwise, to use, you will need to manually install. To do this, you will need to check/update the FSX DLL.XML file to add an entry to the location of the dll (usually your 'modules' folder, under the FSX main folder), and also maybe manually create the FSUIPC4.key file with your license details (if you don't already have one). I can help with both if you need further assistance.

Regards,

John

Attachment : FSUIPC4957b.zip

This post was modified 2 weeks ago by FSUIPC Support